
Gas5_jL 
Book. H iS 



U^Tvl 



THE 



STEAM ENGINE, 



ITS ORIGIN AND GRADUAL IMPROVEMENT, 



FROM THE TIME OF HERO TO THE PRESENT DAY ; 



ADAPTED TO MANUFACTURES, LOCOMOTION AND NAVIGATION. 



BY P. R. HODGE, C. E, 



WITH NUMEROUS EXPLANATORY WOOD CUTS, AND A 
VOLUME, CONTAINING 

FORTY-EIGHT PLATES, 



NE W-YORK: 
D. APPLETON & CO., 200 BROADWAY. 
1840. 



i \J 



Entered, according to Act of Congress, in the year 1840, 

BY D. APPLETOR & CO. 

In the Clerk's Office for the Southern District of New- York. 






(* 



tftf 7 - 



Btixcatti 



£*i 



-3? 



THE MECHANICS OF THE UNITED STATES OF AMERICA, 



BY THE AUTHOR. 



INTRODUCTION. 



To supply the Mechanic with a concise history of the 
invention and subsequent improvements of the Steam Engine, 
from the earliest period to the present time, together with 
such practical rules and explanations as would enable him to 
design and construct a machine of any required power, and of 
the most improved form, for whatever purpose desired, has 
been the main object of the Author of this volume. 

For the purpose of rendering the reference from the letter- 
press to the plates as convenient as possible, it was deemed 
advisable to have the engravings in a separate volume, thereby 
enabling the author to have them of such a size as would be 
practically useful to the workman, instead of being merely 
illustrations of the letter-press. 

The plates being all drawn to certain scales, the dimen- 
sions of every part may be taken and machines built from any 
of the designs. 



VI INTRODUCTION. 

The various engines have been selected as being the most 
improved of their respective classes, and with four exceptions 
only, are all of American construction and arrangement ; thus 
exhibiting, for the first time, the rapid march of improvement 
which this enterprising country has taken during the last few 
years in the science of engineering. 

How far the Author may have succeeded in his endeavours 
to supply this desideratum — " A practical work on the Steam 
Engine" — is a question to be decided by the intelligent and 
and enlightened citizens of the United States. 

New-York, Oct. 1840. 



THE 



STEAM ENGINE, 



P. R. HODGE, C. E. 



PART I. 



HISTORICAL ACCOUNT OF THE 

STEAM ENGINE, 

FROM THE EARLIEST PERIOD TO THE 



PRESENT TIME. 



HISTORICAL ACCOUNT 



STEAM ENGINE, &c. 



From the earliest ages, mankind must have been acquainted 
with the fact, that the application of heat would turn water into 
vapour, and that such vapour would rush through any aperture in 
the vessel containing it, with a considerable degree of force ; 
but the application of this vapour to useful purposes, the employ- 
ment of this force as a mechanical agent, is comparatively of 
recent date. 

Figure I. 




Hero the elder, who nourished at Alexandria in the reign of 
Ptolemy Philadelphus, about 130 years before the Christian 



12 



HERO, OF ALEXANDRIA. 



era, and was eminently distinguished for his learning and for 
the number and ingenuity of his mechanical inventions, is the 
first who gives any account of the application of the vapour of 
water. In his work, entitled Spiritalia, or Pneumatica, he 
describes, amongst many others, two machines which operate 
by the force of steam. The first (figure 1) is a caldron or 
vase C, containing boiling water, with a pipe P reaching nearly 
to its bottom. As the steam accumulates in the top of the 
vessel, it presses on the surface of the water, and will force it 
in a continued jet through the pipe, till the whole is ejected or 
converted into steam. A fountain may thus be formed capable 
of supporting the ball B. 

Fig. II. 




The second (fig. 2) consists of a similar vessel C, which is 
closely covered with a lid, having two pipes A A, which after 
rising vertically for a short distance, are bent towards each 
other, and serve as pivots to support the hollow arms B B, in 
which are openings corresponding to those in the pipes. These 
arms are furnished with two open tubes, and placed diametri- 
cally opposite to each other, and bent at their extremities in con- 
trary directions, and at right angles to the axis of the globe. 
The stream from the water in the vessel rises through the pipes 
into the globe, and issuing through the tubes causes the globe 



CELIPILE. 13 

to revolve, in the same manner as water produces the rotary 
motion of Barker's mill. Though this apparatus is described 
as a mere philosophical toy, and not the slightest hint is given 
that the invention was capable of any useful application ; it is 
curious, as being the earliest instance we are acquainted with, 
of the employment of steam to produce motion ; thus conferring 
on Hero the honour of having invented and constructed the first 
steam engine. Hero also expressly ascribes the sounds which 
issued from the statue of Memnon to the action of steam. If 
this be correct, we have an instance of the application of steam 
to (we will not say a useful, but to) a specific purpose, as early 
as 1600 years before Christ. But we are of opinion with Pro- 
fessor Renwick, " that this is rather an ingenious explanation 
by the philosopher himself, of the mode in which he could have 
effected the same object, than an account of what was really 
performed by the Egyptian priests." 

The description of these machines sufficiently establishes the 
fact, that the ancients were acquainted with both the expansive 
and impulsive force of steam. Our information from other 
sources is exceedingly scanty and imperfect, and is chiefly in- 
cidental. The Oelipile appears to be the only instrument used 
by them to display its power, and that was applied to only one 
object : to excite combustion. How it was used for that pur- 
pose is not explained, and, as steam itself will not support com- 
bustion, remains a matter of conjecture. Vitruvius, in his trea- 
tise on Architecture, Lib. 1. Cap. VI. refers to the oelipile as 
an illustration of the causes of winds. 

Fig. 3 is a representation of this instrument ; which consists 
of merely a globe or other hollow vessel A, containing a small 
quantity of water, and having spouts or tubes, B B. The ves- 
sel being placed over a fire, the water is converted into steam 
and will issue forcibly from the tubes. If the oelipile be placed 
on wheels, it will recoil by the reaction of the steam, as it 
escapes ; and a rotary motion may be obtained by employing 
two tubes, as in the machine of Hero. In this form it is called 
the whirling oelipile. 



14 



CARDAN AND MATHESIUS. 
Fig. III. 




We find no further notice of steam being applied to any pur- 
pose, either of use or amusement, till after the revival of learn- 
ing ; and the earliest modern writers we meet with who speak 
of its mechanical properties, are Cardan and Mathesius. The 
latter, in a volume of sermons, published about 1760-63, hints 
at the possibility of constructing an apparatus similar in its opera- 
tion and properties to the modern steam engine, and " displayed 
almost as much ingenuity in contriving to introduce so unto- 
ward a subject into a sermon as would be required to invent 
the machine itself, and which he gives as an illustration of 
what mighty effects could be produced by the volcanic force of 
a little imprisoned vapour." 

Cardan, who (to quote Renwick) "united all the learning of 
his age to even more than all its superstition," is the first among 
the modern writers who mentions the celipiles, and seems to 
have been acquainted, not only with the expansive force of 
steam, but also the fact that a vacuum could be produced by its 
condensation. About thirty years after this period, the "whirl- 
ing oelipile" is proposed to supersede the turnspit dog in the 
honorable discharge of his culinary duties. Whether this sub- 
stitution of machinery for manual labour was prevented by re- 
monstrance or petition on the part of the domestics whom it 
would so cruelly turn out of employment, is not on record ; but, 
from one of the reasons urged for its adoption, it appears that 
in this, as in other cases, the bad conduct and dereliction from 
honesty of some of these useful laborers, endangered the sub- 
sistence of the whole. The projector states that his machine 



BAPTISTA PORTA. 



15 



" eats nothing, and gives, withal, an assurance to those partaking 
of the feast, (whose suspicious natures nurse queasy appetites,) 
that the haunch has not been pawed by the turnspit (in the 
absence of the housewife's eye,) for the pleasure of licking his 
unclean fingers." 

Fig. IV. 




The next we find worthy of notice is Baptista Porta, a Nea- 
politan. He describes his apparatus in an Italian translation of 
Hero's work, published 1606. It is remarkable as being the 
first in which the steam is applied to force up cold water from 
a separate vessel, instead of driving up the hot water, from 
which it is produced. The boiler A (fig. 4) has a neck or tube 
B, through which the steam passes to the upper part of the 
close cistern C, and, passing on the surface of the water it con- 
tains, forces it up the pipe or syphon D. The contrivance in 
this respect is similar to, and would seem to be the germ of, that 



16 



SOLOMON DE CAUS. 



of the Marquis of Worcester, from which it differs but little, 
except in the extent of its power. 
Fig. V. 




In 1615, Solomon De Caus, a native of Normandy, eminent 
as an engineer and mathematician, published a work on Moving 
Forces and Machines, in which is to be found the following 
contrivance for applying the expansive force of steam. He 
says : " Let there be a globe A, (fig. 5) having a valve B to 
introduce water, and a tube C soldered into the upper part of 
the ball, and descending nearly to the bottom. After having 
filled the ball with water, and well closed the valve, place it 
on the fire ; then the heat acting on the ball will cause the 
water to ascend through the tube." This apparatus (on which 
M. Arago claims for the French the honor of inventing the 
steam engine) is not only inferior to that of Porta, but had 
been anticipated in all but the valve by Hero. 

De Caus was also acquainted with the fact that steam could 
be condensed into its own weight of water ; but he appears 
to have known no mode of applying this property to aid the 
effect of his fountain. 

The machine of Giovanni Brancas, an eminent Italian 
mathematician, who lived at Rome in the commencement of 
the seventeenth century, next claims our attention, being the first 
in which the power of steam was proposed to be used for any 



GIOVANNI BRANCAS. 



17 



other purpose but that of raising water. His machine was 
applied to pounding drugs, and he published his account of it 
in 1629. It consisted of an celipile (fig. 6), the blast of which 
was directed against a wheel formed with float-boards, or vanes, 
similar to a water-wheel or wind-mill. A rotary motion was 
thus produced, which, by the aid of intermediate mechanism, 
worked the stampers or pounders. We afterwards find Bishop 
Wilkins and Father Kircher proposing similar machines — the 
latter recommending to employ two celipiles ; and Philibert 
de l'Orme proposing to use the blast of the oelipile to drive 
smoke up a chimney. 

Fig. VI. 




A note to a Spanish work lately published, consisting of original papers 
relative to the voyages of Columbus, contains a very curious account of an 
experiment made at the port of Barcelona, in the year 1543, in the presence 
of the Emperor Charles V., Prince Philip, and several officers of state. A 
ship of 200 tons burden was propelled by machinery, and it is stated that the 
experiment was altogether so successful, and that the ship tacked so expertly, 
that the Emperor and his suite highly applauded the performance, and Garey 
was handsomely rewarded. The whole of the engine could not be seen, but, 
from the part exposed, it was observed to consist of a large vessel of boiling 
water, with moveable wheels at each side of the ship. When the exhibition 
was over, Garey took the engine from the ship, and, depositing the wood-work 
in the arsenal of Barcelona, kept the rest himself. 

This account, copied from the Royal Archives of the city of Salamanca, 
was communicated to the author of the work, August 27, 1825, by one 
Thomas Gonzales. According to Sir Richard Phillips, the facts cannot be 
3 



18 MARQUIS OF WORCESTER. 

These were the only methods suggested for the application 
of steam to mechanical purposes previous to that of the Marquis 
of Worcester. How far they had been put in practice, or, in- 
deed, if any one of them had been actually used, is very doubtful ; 
but the Marquis most undoubtedly did succeed in constructing 
a machine for raising water, in which the expansive force of 
steam was employed as a source of motion. His account of 
the invention is contained in a work, the original manuscript of 
which is preserved in the British Museum. It is entitled " A 
Century of the Names and Scantlings of Inventions," and was 
written in 1655, and first appeared in print in 1663. We there 
find the following Name and Scantling : 

"LXVIII. A Fire Water- Work. — An admirable and most 
forcible way to drive up water by fire, not by drawing or suck- 
ing it upwards ; for that must be, as the Philosopher calleth it, 
infra splicer am activitatis, which is but at such a distance. 
But this way hath no bounder, if the vessels be strong enough ; 
for I have taken a piece of a whole cannon, whereof the end 
was burst, and filled it three-quarters full of water, stopping 
and screwing up the broken end, as also the touch-hole, and 
making a constant fire under it; within twenty-four hours it 
burst and made a great crack ; so that, having a way to make 
my vessels so that they are strengthened by the force within 
them, and the one to fill after the other, I have seen the water 
run, like a constant fountain-stream, forty feet high. One vessel 
of water, rarefied by fire, driveth up forty of cold water. And 
a man that tends the work is but to turn two cocks, that, one 
vessel of water being consumed, another begins to force and 
refill with cold water, and so, successively, the fire being tended 
and kept constant; which the selfsame person may likewise 



doubted — who further observes that the invention was laid aside, " owing to 
the bigotry of an imperial officer, one of those slow sailing intellects which 
in every age obstruct improvement." If it be true, the honor of first navi- 
gating a ship by steam belongs to Blasco de Garey, as also that of construct- 
ing the first efficient steam engine. 



MARQUIS OP WORCESTER. 



19 



abundantly perform in the interim between the necessity of 
turning the said cocks." 

This description is too vague for us to determine the precise 
form of his machine, and in consequence, many ingenious plans 
for the construction of an engine answering the terms proposed 
have been given by different writers. Among these the most 
complete and simple elucidation of the invention is to be found 
in Tredgold, from whom we copy the annexed figure and de- 
scription : 

Fig. VII. 




" B (fig. 7) is the boiler ; C one of the vessels, with a pipe to 
deliver the water to an elevated cistern, D. Now suppose the 
vessel C to be supplied from a cistern of cold water A by a 



20 MARQUIS OF WORCESTER. 

pipe, so that it should be filled on opening the cock E, and after- 
wards closing it ; if, when the steam in the boiler is of sufficient 
strength, the cock F be opened, the pressure of the steam on 
the water in C would cause it to ascend from C, through the 
pipe a, into the cistern D. The vessel C being emptied, and 
the cock F being shut, it would refill with water, on again 
opening the cock E. Another vessel C and its cocks and 
pipes, are necessary to complete the species of water engine 
indicated by the description, and these may be on the other side 
of the boiler." 

We may observe here, that only the expansive power of 
steam is employed, for the Marquis does not appear to have any 
knowledge of condensation. His application of steam was 
necessarily very expensive, from the great condensation pro- 
duced on the steam coming in contact with the cold water. 
His mode of operation was, however, perfectly capable of 
producing the effects stated, he merely raising 20 cubic feet, 
or 1,250 lbs. of water one foot, by one pound of coals, being 
about the 200th part of the effect of good modern engines. 

The Marquis declares, in his title page, that he has " tried 
and perfected" the extraordinary inventions he describes; but, 
from the studied brevity and obscurity of those descriptions, it 
was long doubted whether he really did effect any of the things 
he pretends to. He has been designated as a " fantastic and cre- 
dulous mechanic," and his book pronounced to be " an amazing 
piece of folly ;" however, many of his schemes have been unex- 
pectedly realized in later times, and it has been satisfactorily 
proved, not only that a fire-engine could be constructed, "ful- 
filling the conditions of the enigma, and no more," but that he 
himself had one in successful operation. In 1818 was pub- 
lished a translation of a manuscript left by Cosmo de Medicis, 
Grand Duke of Tuscany, narrating his travels in England, in 
the year 1656, in which we find the following account of this 
machine : 

"His Highness, that he might not lose the day uselessly, 
went again, after dinner, to the other side of the city, extending 



SIR SAMUEL MORLAND. 21 

his excursions as far as Vauxhall, beyond the palace of the 
Archbishop of Canterbury, to see an hydraulic machine, 
invented by Lord Somerset, Marquis of Worcester. It raises 
water more than forty geometrical feet, by the power of one 
man only, and, in a very short space of time, will draw up four 
vessels of water through a tube or channel not more than a 
span in width." 

We think we may now dismiss his lordship, with the ac- 
knowledgment that to him is due the merit of having first prac- 
tically applied the expansive power of steam to purposes useful 
to society. 

In 1682, we find Sir Samuel Moreland endeavouring to obtain 
the patronage of Louis XIV. of France to a scheme for raising 
water by the force of steam, on apparently a similar principle 
to that of Worcester's ; but which he claims as his own. The 
manuscript which contains his proposal is preserved among the 
Harleian MSS. in the British Museum. It is in the French 
language, beautifully written on vellum, and highly ornamented, 
and it purports to be an account of machines for raising water. 
The part which treats of steam is entitled, " The Principles of 
the New Force of Fire, invented by Chevr. Morland, in 1682, 
and presented to his most Christian Majesty in 1683." In 
this year, he exhibited his invention before the French king 
at St. Germains. We have no description of his apparatus 
or its mode of action. His explanation of his theory is as 
follows : — 

" Water being converted into vapour by the force of fire, 
these vapours shortly require a greater space (about 2000 times) 
than the water before occupied ; and sooner than be constantly 
confined, would split a piece of cannon. But being duly regu- 
lated according to the rules of statics, and by science reduced 
to measure, weight, and balance, then they bear their load 
peaceably (like good horses), and thus become of great use to 
mankind, particularly for raising water, according to the follow- 
ing table, which shows the number of pounds that may be 
raised 1800 times per hour, to the height of six inches, by 



22 



CAPTAIN S AVERY. 



cylinders half filled with water, as well as the different diameters 
and depths of the said cylinders. 



Cylin 


ders. 


Weight of the load to be 
raised, in pounds. 


Diameter in feet. 


Depth in feet. 


1 


2 


15 


2 


4 


120 


3 


6 


405 


4 


8 


960 


5 


10 


1875 


6 


12 


3240 



The table is extended to show the amount of water that can 
be raised by any number (from 1 to 90) of the largest of the 
above cylinders, each cylinder being 6 feet in diameter, 12 feet 
in length, and capable of raising 3240 lbs. weight of water. 

He also gives the rate of the expansion of water when con- 
verted into steam at common atmospheric pressures, so nearly 
correct, that we may fairly conclude it to be the result of actual 
and careful experiment. The general character of his state- 
ment, and particularly his mention of the cannon, would lead us 
to conclude that the idea of his projected engine was borrowed 
from the Marquis' work, published twenty years before ; but 
at all events, he is entitled to the merit of being the first accu- 
rate experimenter on the elastic force of steam. 

The next practical application of steam power was made by 
Captain Savery (also an Englishman), who was the first to 
publish a method of producing a vacuum by the condensation 
\ of steam ; and combining this with the elastic force employed 
\ by Worcester, he constructed an engine for raising water, for 
which he had letters patent granted in 1698; being the first 
patent on record for a steam engine. In 1699, he published a 
pamphlet, entitled " The Miner's Friend," in which he described 
his machine, several of which, according to Dr. Robison, had 
been erected previous to the patent being obtained. In June, 
the same year, he exhibited a model of his engine before the 






CAPTAIN SAVERY. 



23 



members of the Royal Society, who were perfectly satisfied 
with the success attending his experiments. 



Fig. VIII. 




It consisted of a furnace and boiler B (fig. 8) ; from the 
boiler two pipes, provided with cocks C, proceeded to two 
steam vessels S, which had branch pipes from a descending 
main D, and also to a rising main pipe A ; each pair of branch 
pipes had valves a, b, to prevent the descent of the water raised 
by the condensation, or by the force of steam. Only one vessel 
S is shewn in the cut, the other being immediately behind it. 
One of the steam vessels being filled with steam, condensation 
was produced by projecting cold water from a small cistern E 



24 



CAPTAIN S AVERY. 



against the vessel, and into the partial vacuum made by that 
means, the water by the pressure of the atmosphere was forced 
up the descending main D from a depth of about twenty feet ; 
and on the steam being let into the vessels again, the valve b 
closed, and prevented the descent of the water ; while the steam, 
having acquired force in the boiler, its pressure caused the water 
to raise the valve a, and ascend to a height proportional to the 
excess of the elastic force of the steam above the pressure of 
the air. 

g, The guage cock for ascertaining the level of the water. 

In subsequent engines, he employed only one steam vessel, 
and further improved his, machine by the application of Papin's 
digester or safety valve V, and making use of a small boiler to 
heat water for the large one, in order to prevent loss of time. 

It is uncertain whether Savery was acquainted or not with 
the ideas of his predecessors. His claims to originality, and to 
the discovery of condensation, have been much questioned by 
Desaguliers, who also charges him with having bought up and 
destroyed all the copies of Worcester's book on which he could 
lay hands, in order to keep to himself the whole credit of the 
invention. This grievous charge, as Dr. Robison well observes, 
ought to be substantiated by very distinct evidence — "yet 
Desaguliers produces none such ; and he was too late to know 
what happened at the time." Besides, Savery's own account 
is so clear and distinct ; such a liberal and honest appeal to ex- 
periment pervades the whole ; and it is so free from the self- 
sufficiency and conceit too generally to be found in works of 
che kind, that we cannot help giving credit to his statement. 

Under any circumstances, his original invention was con- 
siderable, and his machine very superior to that of the Marquis. 
To him is due the merit of the first use of condensation and the 
safety valve, the employment of a vessel to supply the boiler 
with hot water, and the use of the guage cock to ascertain the 
quantity of water in the boiler. 

The defects of his machine were, great waste of steam from 
the cold vessel and cold fluid ; and the machinery could not be 



DR. DENYS PAPIN. 



25 



made available for mining purposes, as water could not be raised 
to a sufficient height without the use of such powerful steam as 
to become dangerous. 

In 1690, Dr. Denys Papin, a French Protestant, first sug- 
gested using the alternate action of steam and air to produce 
motion. He proposed " turning a small surface of water into 
vapour by fire, applied to the bottom of the cylinder which con- 
tains it, which vapour forces up the plug or piston in the cylin- 
der to a considerable height ; and which, as the water cools, 
when taken from the fire, descends again by air's pressure, and 
is applied to raise water out of the mine" — a mode of operation 
so impracticable, that notwithstanding the aid he received from 
Libnitz, in prosecuting the idea, he was obliged to abandon his 
scheme. It appears that, in 1698, by command of Charles, 
Landgrave of Hesse (to whom he gives the credit of the first 
idea of a steam engine), he made several experiments, but 
without any useful result. Having seen an engraving of Sa- 
very's engine in 1705, he resumed his experiments, and pub- 
lished a tract on the subject in 1707; but notwithstanding his 
knowledge of what Savery had done, his most improved engines 
were incapable of performing more than had already been ac- 
complished by Worcester. 

Fig. IX. 




His machine consisted of a boiler B (fig. 9), provided with 
a safety valve V, and a cylinder G H, connected to the boiler 
4 



26 AMONTONS. 

by the steam pipe S. The cylinder was closed at the top, and 
contained a floating piston P ; and the base of the cylinder ter- 
minated in a curved tube T, which ascended into a cylinder M ; 
the bent tube had a pipe Y from a reservoir of water communi- 
cating with it, and it was provided with a valve at r. Now 
suppose the cylinder G H to be filled with cold water by the 
pipe Y from the reservoir, and the boiler to contain strong 
steam ; by opening the cock E, the steam would be admitted, 
and pressing on the floating piston P, cause the water to ascend 
in the cylinder M ; its return is prevented by the valve K, and 
the steam cock E being shut, and the cock R opened to let the 
condensed steam escape at the pipe R, the water from the reser- 
voir refills the steam cylinder through the pipe Y, and is ready 
for repeating the operation. The water raised can be directed 
to any useful object by the pipe D. 

He is principally famous as the inventor of the safety valve 
and the four-way cock, without the former of which, it is not 
improbable that steam would have been abandoned long ago as 
a most dangerous and ungovernable agent. Mankind are, more- 
over, considerably indebted to him for his proposal to use the 
joint powers of steam and air. This idea, when actually reduced 
to practice by Newcomen in his atmospheric engine, was pro- 
ductive of such favourable and beneficial effects, that the atten- 
tion of scientific men was irresistibly attracted to steam power, 
and a course of experiments and investigations entered on, 
which otherwise they might never have been induced to attempt. 
Dr. Papin also suggested that the water raised by his engine 
might be used to turn a wheel, and so impel other machinery. 

Amontons, a distinguished member of the French Academy 
of Sciences, presented to that body, in 1699, an account of an 
invention, which he calls a Fire Wheel, and which has induced 
most writers on the subject to place his name among the inven- 
tors of the steam engine ; but the machine he describes can be 
considered as nothing but an air engine. He proposes, by the 
alternate application of fire and cold water, to cause an expansion 
and contraction of air, so as to produce motion. 



NEWCOMEN AND CAWLEY. 27 

Notwithstanding the imperfections of Savery's machines, it 
now became sufficiently evident that steam could be used effect- 
ively for raising water, and the want of some cheap and power- 
ful agent for that purpose, rendering the working of deep mines 
so expensive, as to be almost ruinous to the proprietors, though 
otherwise highly productive. An immense prospect of ad- 
vantage opened to any one who could, either by overcoming 
the defects in Savery's invention, or by otherwise adapting 
the power of steam, succeed in obtaining sufficient power to 
work such mines profitably. These incentives producing fur- 
ther researches and experiments, the result was a new con- 
struction of the steam engine, by Thomas Newcomen, a smith, 
of Dartmouth, Cornwall ; and in 1705, he obtained a patent for 
his invention, conjointly with John Cawley, a plumber, also of 
Dartmouth, and Captain Savery, who was associated with them 
on the ground that their machine interfered with his previous 
patent. The principal novelty of this construction consisted in 
condensing the steam under an air-tight piston in a cylinder 
open at top : thus applying atmospheric pressure. The idea 
was probably borrowed from Papin ; for Dr. Hook, who was 
well acquainted with Papin's speculations and experiments, 
seems to have held a correspondence with Newcomen on the 
subject of steam power. However, Newcomen' s mode of effect- 
ing his object was altogether different from any proposed by the 
Frenchmen. The following is a description of Newcomen's 
engine in its improved state. 

"B (fig. 10) represents the boiler, with its furnace for pro- 
ducing steam ; and at a small height above the boiler is a steam 
cylinder C of metal, bored to a regular diameter, and closed 
at the bottom, the top remaining open. A communication is 
formed between the boiler and the bottom of the cylinder, by 
means of a short steam-pipe, S. The lower aperture of this 
pipe is shut by the plate p, which is ground flat, so as to apply 
very accurately to the whole circumference of the orifice. This 
plate is called the regulator, or steam-cock, and it turns hori- 
zontally on an axis, <z, which passes through the top of the 



28 



NEWCOMEN AND CAWLEY. 



Fig. X. 




boiler, and is fitted steam-tight, and has a handle to open and 
shut it. A piston P is fitted to the cylinder, and rendered 
air-tight by a packing round its edge, of soft rope, well filled 
with tallow, to reduce the friction, and its upper surface is kept 
filled with water to render it steam-tight. The piston is con- 
nected to a rod P A, which is suspended by a chain from the 
upper extremity D of the arched head of the lever, or work- 
ing beam, which turns on the gudgeon G. This beam has a 
similar arched head E F at its other end, for the pump rod H, 
which receives the water from the mine. The end of the beam 
to which the pump-rod is attached, is made to exceed the 
weight and friction of the piston in the steam cylinder ; and, 
when the water is drawn from such a depth, that the steam 
piston is too heavy for this purpose, counterpoise weights must 
be added at F, till the piston will rise in the steam cylinder, at 



NEWCOMEN AND CAWLEY. 29 

the proper speed. At some height above the top of the cylin- 
der is the cistern L, called the injection cistern (supplied with 
water from the forcing pump H). From this descends the in- 
jection pipe M, which enters the cylinder through its bottom, 
and terminates in one or more small holes at N. This pipe has 
a cock at O, called the injection cock, fitted with a handle. At 
the opposite side of the cylinder, a little above its bottom, there 
is a lateral pipe, turning upwards at the extremity, and provided 
with a valve at V, called the snifting valve, which has a little 
dish round it to hold water for keeping it air-tight. There pro- 
ceeds also from the bottom of the cylinder a pipe q, of which 
the lower end is turned upwards, and is covered with a valve ; 
this part is immersed in a cistern of water called the hot 
well, and the pipe itself is called the eduction pipe. To regu- 
late the strength of the steam in the boiler, it is furnished with 
a safety valve, constructed and used in the same manner as that 
of Savery's engine, but not loaded with more than one or two 
pounds on the square inch." 

Mode of Operation. — " The piston being at the bottom of the 
cylinder, and the regulator or steam-valve being shut, it will be 
kept there by the pressure of the atmosphere. Apply the fire 
to the boiler till the steam escapes from the safety valve, and 
then, on opening the steam-regulator, the piston will rise by the 
joint effect of the strength of the steam and action of the 
excess of weight on the other end of the beam. When it 
arrives at the top of the cylinder, close the regulator p, and by 
turning the injection-cock O, admit a jet of cold water, which 
condenses the steam in the cylinder, forming a partial vacuum, 
and the piston descends by the pressure of the atmosphere, 
raising water by the pump rod from the mine. The air which 
the steam and the injection water contains is impelled out of 
the snifting valve V, by the force of the descent, and the injec- 
tion water flows out at the eduction pipe Q ; and by the repe- 
tition of the operations of alternately admitting steam and 
injecting water, the work of raising water is effected." 

The steam was condensed in his early engines by the appli- 



30 HUMPHREY POTTER. 

cation of cold water to the outside of the cylinder. Desaguliers 
says, the idea of injection was the result of accident — " as they 
were working they were surprised to see the engine go several 
strokes, and very quick together ; when, after a search, they 
found a hole in the piston which let the cold water in to con- 
dense the steam in the inside of the cylinder ; whereas, before 
they had always done it on the outside." This being observed, 
the injection cock was soon added to the machine. 

A further improvement is the addition of contrivances for 
opening and shutting the cocks and valves by the action of the en- 
gine, thus rendering it more nearly a self-regulator, was brought 
about through the idle ingenuity of a boy named Humphrey 
Potter ; who, that he might have time to play, found means to 
open and shut them by attaching strings and catches to the 
working beam. The engine was brought to this simple and 
efficient degree of perfection about 1712, and such engines 
were erected in several places. It was called, in this state, 
the Atmospheric Engine. 

The merit of this engine has been said to lie chiefly in its 
mechanism, but that mechanism makes it efficient, and there- 
fore practically of much value. It is one thing to suggest the 
particular application of a certain principle, and another to fol- 
low out such suggestion to a practical result. Tredgold very 
pertinently remarks : 

" To point out what is actually due to Newcomen would be 
difficult ; and, for want of evidence, we must be content with 
examining the state of the engine. The admission of steam 
below an air-tight piston, attached to the impelled point of a 
lever properly counterpoised ; its rapid condensation by the 
injection of water, which is essential to gain effect ; and the 
mode of clearing the cylinder of air and water after the stroke, 
are all additional to the principles and mechanism before in use, 
and these are wholly due to Newcomen, or those connected 
with him." 

Henry Beighton, an engineer of Newcastle-upon-Tyne, di- 
rected the construction of several engines. He was the first 



HENRY BEIGHTON. 31 

who reduced the calculation of steam power to any regular sys- 
tem. The table published by him in 1717, of "the Dimensions 
and Power of the Steam Engine," has been found to be generally 
correct. It was Beighton who first noticed the fact that steam 
would heat a considerable quantity of water during condensa- 
tion. He made many experiments as to the bulk of steam pro- 
duced from a given quantity of water, and communicated his 
experiments to Desaguliers, but from a mistake in his cal- 
culation his result was incorrect. He improved the machinery 
for opening and shutting the valves, which before him was 
little more than the contrivance of the boy Potter, consisting 
merely of strings and catches. Beighton first adopted rods, 
connected with the working beam. He also evinced much 
judgment in his manner of fixing engines, and his arrangement 
of the different parts. His views were not very novel, but he 
possessed sound scientific knowledge, which, perhaps, was pro- 
ductive of more practical good. 

The accounts we have of different engines by various pro- 
jectors about this time, are sufficiently numerous ; but as they 
do not contain any thing new, either in theory, experiment, or 
construction, they are hardly worthy of notice. But an illustri- 
ous German, named Leupold, was a man of superior character. 
His engine, constructed 1720, is admirable for its extreme sim- 
plicity, but is more remarkable, from being the first combination 
of the working beam and cylinder with the high-pressure prin- 
ciple, thus constituting the earliest high-pressure engine. 

Over a boiler B (fig. 11), he placed two cylinders C C, fitted 
with steam-tight pistons PP. A four-way steam-cock S is 
placed between the boiler and cylinders, so as to alternately 
admit steam into one cylinder and let it out from the other. 
The piston, by the admission of strong steam from the boiler 
below it, is raised, and depresses the other end of a lever con- 
nected to the rod of a plunger of a pump, which causes the 
water to rise through the pipe, and, by the alternate action of 
the steam in the two cylinders, a continual stream of water is 
raised. As Papin was the inventor of the four-way cock, and 




the first who proposed to raise a piston by steam, Leupold, 
with a rare degree of modesty and candour, ascribes the merit 
of this machine to him, but the mode of working out the prin- 
ciple is certainly due to his own ingenuity. 

Dr. Desaguliers wrote much, but added nothing to the exist- 
ing knowledge of the steam engine ; though we might have 
expected much, from his fondness of experimental philosophy, 
and the opportunities he had of knowing what was going on in 
the scientific world. He was, besides, much prejudiced for and 
against individuals ; his work is, therefore, only valuable as a 
depository and record of facts. 

By this time, the atmospheric engine, with Beighton's im- 
provements, was in very general use for raising water from 
coal and copper mines, but, excepting the experiment of Blasco 
de Garey [see note, p. 17,] there does not appear to have been 
any attempt to apply steam power to any other useful purpose. 
Savery, indeed, among other suggestions, hints at the possi- 
bility of employing this mighty power in navigation, but says 
he dare not meddle with that matter ; and he leaves it to " the 



JONATHAN HULLS. 33 

judgment of those who are the best judges of maritian 
affairs." With these exceptions, Jonathan Hulls, of London, 
is entitled to the merit of being the first who proposed or 
attempted the construction of a steamboat. He obtained let- 
ters patent for his project, in 1736, and published them, with a 
description of his boat, in 1737, in a tracts which is now ex- 
tremely scarce, entitled, " A description and Draught of 
a new-invented Machine for carrying Vessels or Ships out 
of, or into, any Harbour, Port, or River, against Wind or Tide, 
or in a Calm." He contrived a method of converting the recip- 
rocating motion of the piston into a continuous circular motion. 
Tredgold gives a cut of this invention, and very justly remarks, 
that, though it is less simple than the crank, it is " certainly a 
beautiful contrivance for rendering so irregular a first mover 
equitable, and, considering the object it was intended for, it is 
not a complex arrangement ; for, besides equalizing the power, 
it gives a means of increasing or diminishing the velocity in 
the ratios of the diameters of the wheels." 

" Let a, b, c (fig. 12), be three wheels on one axis, and d, e two 
wheels loose on another axis A, with ratchets, so as to move 
the axis only when they move forward ; /, g, h are three ropes, 
and P is the piston of the engine. When the piston descends, 
the wheels a, b, c move forward, and the ropes g, h cause the 
wheels e, d to move the wheel e forward, and the wheel d 
backward, and the latter raises the weight G, which moves the 
wheel d forward during the descent of the piston ; consequently, 
the axis A B, with the paddle-wheels, would be constantly 
moved round in the same direction and with an equable force." 

From the ingenuity and information displayed in his little 
work, we feel assured that Hulls was a man of considerable 
ability, and cannot help regretting that his views should have 
shared the fate of too many other useful projections, in not 
meeting the encouragement they so evidently merited. 

Though our sketch is intended to be confined to those who 
either theoretically or practically improved the steam engine, 
we cannot altogether pass by Belidor, an eminent French writer 



34 




on Engineering, civil and military ; who deserves mentioning, 
on account of his historical sketch of the steam engine (1739). 
He very industriously and candidly examines the different 
claims to the honour of the invention, and concludes that it be- 
longs to the Marquis of Worcester ; who, he says, first gave 
the idea to the world in an intelligible form. After giving a 
description of an engine erected at Frisnes, near Condi, he 
states that up to that time all fire engines, whether constructed 
in or out of England, had been made by English workmen. 
His work is valuable from its extensive research, and the 
minute, clear, and practical style in which it is written — a style 
almost peculiar to himself, and which distinguishes all his pro- 
ductions. In other respects the book is of little use, as he 
added nothing to the existing knowledge of the action of 
steam ; and his rules for the calculation of steam power are 
both complicated and inaccurate. 

The first attempts, by direct experiment, to ascertain the 



JOHN PAYNE. 35 

density of steam, were made by John Payne, and an account 
of them published in the Philosophical Transactions, vol.41. 
(1741.) His process was ingenuous, but, from neglecting to use 
a thermometer, the results were unsatisfactory. 

" He took a copper globe, twelve inches in diameter, having 
two cocks fitted to it, and a small valve. The vessel thus 
prepared was hung over a large vessel, in which water was 
rarefied into steam, and by a pipe the steam was admitted at 
one of the cocks into the globe, and the other being also open, 
the steam being allowed to blow through, forced out the air 
that was in the globe, and supplied its place ; when both cocks 
were suddenly shut, and the globe taken down and hung over 
a vessel of cold water, with the lower cock immersed in water. 
The cock was opened under water, on which the water rushed 
violently into the globe, till it had supplied the vacuum, when 
the cock was again shut, and the globe, with the water, was put 
in the scales, and found to weigh 713 ounces, which, taken 
from 727 ounces, the whole weight before, there remains only 
14 ounces for the difference ; from which he inferred that all 
the air was nearly excluded out of the globe by the steam. He 
again excluded the air out of the globe with steam as before, 
and both the cocks being closed, with the globe full of steam, 
he put the globe in the scale, and it weighed 2035 ounces. He 
then opened one of the cocks, and let in the air, and by adding 
weight in the other scale, it was found to weigh 203 ounces, 
which showed that the weight of the air the globe contained 
was 5 ounces, or 218.75 grains. The globe being filled with 
steam as before, and condensed with cold water on the outside 
of the globe, and the metal again made very dry, and the air let 
into the globe, the water from the condensed steam was found to 
weigh 96 grains. It is worthy of remark here, that this gives 
the density of steam at 212° to that of air at 60°, as 96 : 218. 
75, or, as 0. 44: 1. The true density of steam at 212° is 
nearly as 0. 48: 1. 

The globe was filled with steam as before ; only, not know- 
ing the effect of temperature, he continued the globe longer 



36 JOHN PAYNE. 

with the steam passing through it, by which it acquired a 
greater degree of heat ; for he found by these experiments, that 
the least degree of cold, less than the steam, would condense 
a part of it again into water, and hence the quantity could 
not be ascertained which would exclude the air out of a given 
space, which was the chief end of the experiment. In this 
experiment, he succeeded in excluding the air with less steam ; 
for, on weighing the globe, when the steam was condensed, the 
air let in, and all cold, it was found that the weight of the 
water condensed from the steam was only about 48 grains, 
which filled, when converted into steam, 925 cubic inches of 
space, so as to exclude nearly all the air. From which he con- 
cluded that one cubic inch of water will form 4,000 inches of 
steam. To admit of comparison, the temperature should have 
been observed, as there is little doubt that the steam was so 
rarefied by heat as to cause this result. 

He also first proposed the mode of generating steam by dis- 
persing water in small portions over a heated surface. 

" His apparatus consisted of a cast iron vessel, of the figure 
of a frustrum of a cone, its diameter at the bottom being four 
feet, with a semi-globular end of copper, of about four feet 
and a half in diameter. In the inside a small vessel was in- 
serted, which Payne calls a disperser, which vessel had pipes 
round the sides fixed to it ; the bottom rested on a central pin, 
on which it revolved, so as to spread the water it received from 
above, through an iron pipe. The end of this pipe passed up 
through the head, and was enclosed very tightly, but so as to 
be very easily moved with a circular motion, so that the water 
might be dispersed or showered round on the sides of the red- 
hot cone, or ignited vessel, in a very exact manner. From ex- 
periment he states that a pot or vessel, of the size and shape 
here mentioned, will, being kept to a dark red heat, and the 
water regularly dispersed, convert 6.5 cubic feet of water into 
steam in an hour. And that by experiments made at Wednes- 
bury and Newcastle-upon-Tyne, 112 pounds of pit coal will, 
by this method, convert 12 cubic feet of water into steam." 



GENSANNE.— DE MOURA. 



37 



This idea has been revived in the present day by Mr. 
Howard. 

Though machinery had long superseded the necessity of 
personal attendance for opening and shutting the valves of 
Newcomen's engine, it appears that nothing of the kind had 
been applied to Savery's engines. The first self-acting appa- 
ratus for that purpose was invented in 1744, by one Gensanne, 
a Frenchman. Fig. 13 represents this contrivance. X is the 
receiver ; H, a pipe rising from the cistern; G, the eduction pipe ; 
F, the injection pipe ; C, lever of injection cock ; B, the axis of 
the steam valve N, which slides horizontally ; M, top of boiler ; 
D D, two tumbling bobs, performing the same office as in the 
atmospheric engines ; A A, levers ; E, handle of steam valve. 

From the maimer in which the levers are connected, their 
simultaneous operation may be easily perceived. Another 
method is ably described by Smeaton, in the Philosophical 
Transactions, 1751. It was by a Portuguese, named De 
Moura, who had sent a model of his invention to the R. Society. 




38 F. BLAKE. 

" The engine consists of a receiver, with a steam and an 
injection-cock. It has a suction and a forcing-pipe, each fur- 
nished with a valve and a boiler, which may be of the common 
globular shape. Having nothing particular in its construction, 
a description of it will not be necessary : also, the rest of the 
parts already mentioned being essential to every machine of this 
kind, a further account of them may be dispensed with. What 
is peculiar to this engine, is a float within the receiver, com- 
posed of a light ball of copper, which is not loose in it, but 
fastened to the end of an arm made to raise and fall by the float, 
while the other end of the arm is fastened to an axis ; and, 
consequently, as the float moves up and down, the axis is 
turned round one way or the other. The axis is made conical, 
and passes through a conical socket, which last is fixed to the 
side of the receiver. On one of the ends of the axis, which 
projects beyond the socket, is fitted a second arm, which is 
also moved backwards and forwards by the axis as the float 
rises and falls. By these means, the rising or falling of the 
surface of the water within the receiver communicates a cor- 
responding motion to the outside, in order to give the proper 
motions to the rest of the apparatus which regulates the open- 
ing and shutting of the steam and injection cocks, and serves 
the same purpose as the plug frames, &c, in Newcomen's 
engine." 

In 1751, Mr. F. Blake, F.R.S. published a paper on the best 
proportions for steam engine cylinders, which being one of 
the earliest theoretical inquiries respecting the proportions of 
engines, has just claims to our attention. His reasoning is very 
ingenious. 

" It is evident," he says, " from the principles of mechanics, 
that the contents of the cylinder remaining the same, the quan- 
tity of water discharged at each lift will in all cases be equal ; 
and this equality is obtained by only adjusting the distance of 
the centre of the piston from the fulcrum of the beam. It will 
be granted also, that the excess of the column of atmosphere 
above that of water, is equivalent to a weight on the piston, 



F. BLAKE. 39 

driving it to a depth of about five feet within the cylinder, with 
an accelerated motion, till the friction and resistance from the un- 
condensed steam which remains in the cylinder, even after the 
injection, and which is increased in elasticity while its bounds 
are diminished, shall equal the accelerative force ; and that then 
again, the piston may be retarded the rest of the way. But 
independent of friction, we can, notwithstanding this dimunition 
of force, by the remainder of steam within the cavity of the 
cylinder, demonstrate the ratio of the velocities and the times of 
descent of pistons in cylinders of unequal altitudes to be exactly 
the same as if the resistance were nothing ; whence we shall, 
without difficulty, arrive at some conclusion in this matter. Let 
M N be the working part of a steam engine cylinder of the 
usual height, equal in diameter to a shorter one m n r and the 
rarefaction in both of them being supposed the same, A Q=ag 
may represent the excess of the atmosphere's weight above the 
column of water ; R Q=r q, the resistances of the pistons from 
the remainder of the steam, and A R=cr, the effective forces. 
Make a k : A K : : an:AN, and at all similar positions, the 
resistance be of mn, and force kc on its piston, will be equal 
to the resistance B C of M N, and force KCon its piston ; 
and (by Newton's Princip. prop. 39,) in the descent of bodies, 
we have Vakcr : t/A K C R : : celerity in k : celerity in K, 
But these areas being evidently as the corresponding parallello- 
grams k q and K Q, and these again as their heights, the cele- 
rities generated are in the subduplicate ratio of a k to A K, as 
if the resistance had been invariable. 

" To apply this to steam engines, if T W be a cylinder of 
equal content with the cylinder M N, the quantity of water de- 
livered by both will, as observed above, be the same at each 
lift ; but the cylinder T W is no higher than m n, and their 
rarefactions are supposed equal. Therefore, by what has been 
proved with regard to the times, the time of the piston's descent 
in T W will be to that of the piston's descent in m n : : V E W 
: VA N ; whence, in any given time, the short cylinder TW 
will perform more than the larger one M N of equal content, 



40 



KEANE FITZGERALD. 



and that in the ratio of their diameters ; for, as T E* xE W 
= M A 2 x AN, and E W : A N t ; M E 2 : T E 2 ; therefore, 
VEW : Va. N :: M A ; T E. And the friction is diminished 
with the slowness of the motion because the periphery of the 
piston increases in a less ratio than its area. 

It will be seen from the above that he is in favour of a short 
cylinder ; and taking the subject as he views it, his conclusions 
appear tolerably correct, But as Tredgold very justly observes, 
" The proper question is, What form of the cylinder will enable 
us to do the most work with the least steam, and not the most 
work in the least time with a cylinder of a given capacity ?" — 



Fig. XIV. 



irrii iiiiiib a 








M 




A 33. Q. 




111)11 




li L/ 1 




I 


f 



In a subsequent paper, he investigated the relation between 
the power and resistance which gives a maximum effect in a 
given time when the motion accelerates from rest, both when 
the force is uniform, and when variable, increasing with the 
distance. 

The importance of economy in the use of fuel in such a 
machine as the steam engine, is obvious to every one ; and 
amongst the earliest of those who directed their attention to this 
object, was Mr. Keane Fitzgerald, F.R.S., a gentleman of 
great scientific attainments. Accordingly, in 1757, we find 
him proposing to agitate the water in the boiler by a stream of 
air on the principle of Dr. Hale's plan of evaporation. The 
projection was a failure ; for Fitzgerald had not perceived the 
difference between forming steam and accelerating evaporiza- 
tion ; but its publication caused Hale to consult him respecting 
using the steam engine to work ventilators in mines. 

For this purpose, Fitzgerald contrived a mode of converting 



JAMES BRINDLEY. 41 

the reciprocatory motion of the Atmospheric Engine into a 
rotary one, and which was published in the Philosophical 
Transactions for 175S. The method nearly resembles in prin- 
ciple that contrived by Hulls for his steam boat ; but in Fitz- 
gerald's plan, a fly wheel is used for a regulator instead of a 
weight. 

Up to this time, it had been the usual mode to construct the 
working beam with its axis below the centre of gravity. Fitz- 
gerald pointed out the error, and by altering the place of the 
axis of the beam of the York Water Works Engine, he con- 
siderably increased its efficiency. He also published proposals 
for erecting corn mills, and " mills of all kinds," to be driven 
by steam power ; but his proposals do not appear to have met 
with the confidence of the public. 

The celebrated mathematician, William Emerson, gives in 
his Mechanics (1758), a description of the Atmospheric Engine, 
with the mode of computing its power, as far as statical equili- 
brium between the power and resistance is concerned. The 
article is brief but clear. In his Miscellanies, he solves a pro- 
blem, intended to determine the relation between the power and 
the resistance when the effect is greatest. 

James Brindley, the celebrated engineer, attempted to econo- 
mize fuel by forming the sides and top of the boiler of wood 
and the bottom of stone. The fire-place and chimney were 
made of cast iron and placed inside the boiler, both of them 
being surrounded by the water as far as possible. By these 
means, he expected to render more of the heat of the fuel effect- 
ive, and therefore obtained a patent for the arrangement (1759) ; 
but the rapid destruction of the wood by the steam compelled 
him to abandon his plan, and he afterward had recourse to 
casing iron boilers with wood. His former plans were not 
adopted in general practice, being based on erroneous ideas of 
the quantity of heat and the nature of combustion. 

" It may be stated as follows : — In a steam engine, there is 

given the effective pressure of the atmosphere upon the piston 

and the length of the stroke, to find the water to be drawn at a 
6 



42 DR. BLACK. 

stroke, so that the greatest quantity shall be drawn in a given 
time, supposing the force uniform, and the arms of the beam 
of equal length." This solution differs from that of Blake — " in 
taking the whole time of the ascending and descending strokes 
into the account, and in not considering the moving power as 
a gravitating mass of matter." It is, therefore, more strictly 
applicable to the question, though still not perfectly so, as the 
space, not the time, should be given. 

When we reflect that heat is so general and active an agent 
in all our operations, mechanical and domestic, it is matter of 
surprise that its nature, and the laws which govern its genera- 
tion and transmission, should have been neglected for so long a 
time, and so little the subject of scientific investigation. Bacon, 
in his Novum Organon, exemplifies his method of induction by 
an inquiry into the nature of what he terms, in his quaint but 
expressive phraseology, the " form of heat." He concludes 
that "heat appears to be motion," and it is worthy of remark, 
that his hypothesis is the very same with one of those which, 
after a lapse of two centuries, still divides the opinion of phi- 
losophers. It is still a question whether heat be really matter 
— a subtile fluid, capable of diffusing itself into bodies or any 
thing more than motion, vibration or rotation, excited among 
their particles. The greater part of the facts relating to heat 
may be explained equally well on both suppositions. From 
the time of Bacon till 1762, the subject does not appear to 
have met with much, if any, attention ; excepting in some few 
experiments and contrivances for saving of fuel. At this 
period, the celebrated Dr. Black made known his experiments, 
and began to teach publicly his hypothesis of the materiality 
of heat. To him we owe the first investigation of the combi- 
nation of heat with bodies in the solid, liquid, and gaseous 
state. He showed that the heat so combining with them was 
insensible to the thermometer, and hence he called it latent 
heat. 

He found that the quantity of heat required to convert boil- 
ing water into steam, exceeded five times the quantity required 



JOHN SMEATON. 43 

to make cold water boil. He also found, that to produce the 
same degree of temperature in different bodies, different quan- 
tities of heat were required. This property of bodies he called 
capacity for heat ; it is now usually termed specific heat. 

Dr. Black extended his inquiries into the nature and effect 
of fuel, and taught the principles of managing compound fires. 
Drs. Irvine and Crawford followed up his inquiries, by making 
experiments to determine the specific and latent heat of various 
substances. 

John Smeaton, so justly famous for the Eddystone Light- 
House, and other public works, gave much of his attention to 
the details of the atmospheric engine, and brought it to nearly 
as high a degree of perfection as its principles will admit. 
How far he was acquainted with the discoveries and views of 
Dr. Black, does not appear ; but, if acquainted with them, his 
mind was not of a cast likely to turn them to account. His 
ability was principally displayed in improving the construction 
and proportions of machines already invented, by selecting 
the best methods known, and making careful experiments on 
their mode of operation. In 1765, he designed a portable at- 
mospheric engine for the purpose of making trials upon, which 
seems to have been the first attempt at constructing an engine 
capable of removal from place to place. A tolerable idea of 
this machine may be formed from the following description : 

" The diameter of the cylinder was 18 inches, its area, in cir- 
cular inches, 324 inches, and allowing seven pounds to the inch, 
which such a cylinder, he remarks, would very well carry, we 
have 2,268 pounds. The motion was communicated from the 
piston to the pump-rod by awheel 6.2 in diameter, with a chain 
instead of a beam. The number of strokes per minute is stated 
to be ten, of six feet each ; hence the effect is 2,268 x 10x6= 
136,080 pounds, raised one foot, or four horses' power ; he 
reckoned it equivalent to six horses ; and therefore his value of 
the horse power is 22,680 pounds, raised one foot high per 
minute, instead of the usual standard of 33,000 pounds." 

Respecting fuel, he remarks, it has been found by experience 



44 JOHN SMEATON. 

that a two feet cylinder requires 174 pounds of Newcastle coal 
per hour ; which, reduced in the ratio of the capacity, gives 
ninety-seven pounds and a half per hour for the eighteen inch 
cylinder, or a four horse engine, according to the common ap- 
plication of fire ; but he had reason to think an engine con- 
structed like his would not require above sixty-five pounds per 
hour for a four horse engine. The fire-place was of a spheri- 
cal figure, of cast-iron, and entirely within the boiler ; the 
coals were introduced by a large pipe from the outside of the 
boiler to the fire-place, and the smoke passed off by a curved 
pipe, with an iron funnel, to promote a sufficient draught. The 
ashes fell through a pipe covered by a grate eighteen inches in 
diameter, the whole being joined to the boiler by proper 
nanches, and always covered with water. In so short a flue 
the force of the fire cannot be wholly exhausted within the 
compass of the boiler, therefore the curved pipe was sur- 
rounded by a copper vessel adapted to its shape, into which 
was brought the feeding water, that it might be raised to a 
greater degree of heat than it brought immediately from the hot 
well into the boiler. It is also obvious that, by this arrange- 
ment, the coolest part of the water comes in contact with the 
flue, to take the heat from the smoke before it ascends the 
chimney. The bars of the grate were cast into a loose ring, 
and were capable of being taken out, and replaced when occa- 
sion required. 

He seems to have first introduced the improvements result- 
ing from his experiments early in 1774, and by their applica- 
tion, the expenditure of fuel was reduced about one-third. 
Several large atmospheric engines were erected under his 
direction, which, from their general excellence, and the admi- 
rable manner in which the boilers are adapted for generating 
steam, have not been exceeded in later times. 

In 1775, he designed and erected the famous Chase-water 
engine. It has a 72 inch cylinder, with a 9 feet stroke, and is of 
108 horse power. The estimated consumption is 1,136 pounds 
of Newcastle coal per hour, and it was proposed to make nine 



JOHN SMEATON. 45 

strokes per minute, at its full power, to be regulated by the 
cataract to four and a half strokes per minute. It is particu- 
larly deserving of attention, from the able and curious con- 
struction of the beam. 

In the collection of his papers, purchased by Sir Joseph 
Banks, is to be found a table of the proper proportions of the 
parts of different sized engines ; indeed, few practical circum- 
stances connected with the atmospheric engine escaped his 
inquiry. His most important researches are relative to the 
piston, on which' he remarks, "he had found engines calculated 
to carry a load varying from under five pounds to upwards often 
pounds to the square inch, those lightly loaded being expected 
to go with the greatest velocity ; so that an engine carrying 
five pounds to the inch, must go with double the velocity of 
one loaded to ten pounds, the cylinders being of equal area, in 
order that the effects of the power might be equal." He fur- 
ther adds, that in engines, however, as in other machines, 
there is a maximum which, without new principles of power, 
cannot be exceeded — bad proportions of the parts, and bad 
workmanship, may make an engine fall short, in any degree, 
of what it should do, but its maximum cannot be exceeded by 
the most skilful artist. He concludes that any load will do, if 
the parts be properly proportioned ; but, from a long course of 
very laborious experiments, he had fixed his scale near upon, 
but somewhat under, eight pounds to the inch, including raising 
the injection water. 

The experience of preceding engineers had induced nearly the 
same conclusion. In their first engines, Newcomen and his co- 
partners made the load on the piston a little over eight pounds per 
square inch, but they afterwards diminished it ; and before Smea- 
ton's time, the general rule acted upon, in the construction of the 
best engines, was to load them to about seven pounds on the 
square inch. 

The uses to which he proposed the steam engine should be 
applied, showed the imperfect state of mechanical sciences at 
that time. He proposed to construct a steam engine to raise 



46 BLAKELY. 

water ; the water to be made use of for turning a water-wheel 
to draw up coals ; also to drive a corn mill by water, which 
was to be raised by one of Boulton and Watt's engines, erected 
for the purpose, and we find him using the following reasoning 
on the subject : 

" It is to be apprehended that no motion communicated from 
the reciprocating beam of an engine can ever act with perfect 
equality and steadiness in producing a circular motion, like the 
regular efflux of water in turning a water-wheel ; and much 
of the good effect of a water-mill is well known to depend 
upon the motion communicated to the mill-stones being per- 
fectly equable and smooth : the least tremour or agitation takes 
off from the complete performance. Secondly, he says, all 
the engines he had seen were liable to stoppages, and so 
suddenly, that in making a single stroke, the machine is capa- 
ble of passing from nearly its full power and motion to rest; for 
whenever the steam gets lowered in its heat below a certain 
degree, for want of renewing of the fire in due time or other- 
wise, the engine is then incapable of performing its functions. 
In the raising of water, (a business for which the fire-engine 
seems peculiarly adapted,) the stoppage of the engine is of no 
other ill consequence than the less of so much time ; but in 
the motion of mill-stones grinding corn, such stoppages would 
have had a peculiarly bad effect." 

Watt's new mode of operation, which was now becoming 
pretty generally public, tended much to reduce the value of 
Smeaton's improvements, by nearly superseding the use of the 
atmospheric engine. But, had he done nothing else for man- 
kind, he would be deserving the highest praise for his laborious 
investigations of the subject ; and it must be allowed, that even 
the wonderful inventions of Watt owed much of their practical 
efficiency to his employing the admirable modes of construction 
which Smeaton had applied to the air pump. 

We should be acting unjustly, were we to suffer the name of 
Blakely to pass without notice. In 1776, he obtained a patent 
for a new mode of constructing Savery's engine, by using two 



JAMES WATT. 47 

receivers, one placed over the other, with a pipe of communi- 
cation between them. To avoid the condensation arising from 
the contact of the steam and water, he proposed to introduce 
a stratum of oil on the surface of the water ; because oil did 
not so readily absorb the caloric : thus forming a species of 
fluid floating piston. 

He also proposed the interposition of a body between the 
steam and the water to prevent their coming in contact. The 
celebrated Ferguson delivered several lectures on these sup- 
posed improvements, and great contentions arose amongst almost 
all the scientific men of the day as to the practicability of the 
project ; but it proved a complete failure. Indeed, both methods 
are evidently very inferior to the floating piston of Papin. 

His merit consists in his having been the first to propose 
the use of cylindrical tubes for boilers ; an idea which was 
renovated by Perkins, and which has subsequently been so 
adventitiously adopted in the construction of locomotive engines. 
His description of this invention was published in 1774, and 
in 1793, he published at London a pamphlet, entitled, "A 
Short Historical Account of the Invention, Theory, and Prac- 
tice of Fire Machinery," chiefly filled with short notices of his 
own labours. 

We have now arrived at what may be considered the most 
important and interesting period of our history ; the time when 
the steam engine was improved and remodelled — we may al- 
most say invented — by the genius of Watt. 

This truly illustrious man was born in 1736, at Greenock, 
in Scotland ; his father being a respectable merchant, and 
filling the office of baillie or magistrate of the town, and much 
esteemed in his narrow sphere as a man of great benevolence. 
His grandfather and uncle were both respectable mathemati- 
cians ; the former was a schoolmaster, and the latter is known 
as the author of "A Survey of the Clyde." From his infancy 
Watt was of delicate health, to which, perhaps, in a consider- 
able degree, may be traced the retiring and studious habits for 
which he was so remarkable through life. After going through 



48 



JAMES WATT. 



the usual elementary course of education, which the excellent 
grammar schools of that country afford such facilities for ac- 
quiring, he was, at the age of sixteen, apprenticed to a mathe- 
matical instrument maker, with whom he remained four years. 
This occupation, however, differed widely from what is now 
understood by that term. It included not only the making and 
repairing the general run of mathematical instruments, but also 
making and repairing c'ocks, fishing tackle, all kinds of musi- 
cal instruments, and acting as a rough cutler. At the age of 
twenty, he went to London, and placed himself under a regular 
mathematical instrument maker, with whom he acquired habits 
of dispatch and order in business ; but finding his health de- 
cline, he returned to Scotland at the end of a year, intending 
to settle in Glasgow, and begin business on his own account ; 
but not being a citizen, and the corporation laws of this city 
restricting all exercise of trade to the burgesses, he would have 
been compelled to relinquish his intention, had he not fortu- 
nately obtained the ^appointment of mathematical instrument 
maker to the University. The ancient privileges of this insti- 
tution secured to him the desired immunity from the restriction ; 
and the professors gave him apartments in the college, in which 
he lived and carried on his business. The University pos- 
sessed a philosophical apparatus, together with funds for the 
support of a professor of natural and mechanical philosophy. 
Watt was thus early placed in a situation well calculated to 
excite and develope his peculiar powers ; and as far as we can, 
we shall allow him to give the history of his studies in his own 
words. " My attention," says he, " was first directed in 1759, 
to the subject of steam engines by Dr. Robison, then a student 
in the University of Glasgow, and nearly of my own age. 
Robison at that time threw out the idea of applying the power 
of the steam engine to the moving of wheel carriages, and to 
other purposes ; but the scheme was not matured, and was 
soon abandoned on his going abroad." In 1761-62, Watt made 
his first experiments with steam of a high pressure, and an 
apparatus resembling Leupold's engine ; but " soon relinquished 



JAMES WATT. 49 

the idea of constructing an engine upon this principle, from 
being sensible it would be liable to some of the objections 
against Savery's engine from the danger of bursting the boiler, 
and the difficulty of making the joints tight ; and also that a 
great part of the power of the steam would be lost, because 
no vacuum was formed to assist the descent of the piston." 
His attention being taken up by his regular business, he did 
not make any further experiments till the winter of 1763- 
64, when, being employed by Professor Anderson to repair 
a model of Newcomen's engine belonging to the Natural Phi- 
losophy class, his thoughts were again turned to the subject. 
At that period, he informs us, " his knowledge was derived 
principally from Desaguliers, and partly from Belidor, and he 
set about repairing the model as a mere mechanician ;" but 
when it was done and set to work, he found the consumption 
of steam so great, that the quantity wasted must have been in 
a very large proportion to that used. He at first supposed this 
arose from the circumstance that brass, the metal of which the 
cylinder was composed, was too great a conductor of heat. 
Accordingly, he made some experiments with wooden cylinders 
soaked in linseed oil and baked to dryness ; but he soon found 
that wooden cylinders would not be sufficiently durable. Be- 
sides which, the " steam that was condensed in filling them, 
still exceeded the proportion of that which w T as required for 
engines of larger dimensions. It was also found, that unless 
the temperature of the cylinder itself were reduced as low as 
that of the vacuum, it would produce vapour of a temperature 
sufficient to resist part of the pressure of the atmosphere. All 
attempts, therefore, to produce a better exhaustion by throwing 
in a greater quantity of injection water was a waste of steam ; 
for the larger quantities of injection water cooled the cylinder 
so much, as to require quantities of steam to heat it again, out 
of proportion to the power gained by having made a more per- 
fect vacuum ; and on this account, the old engineers acted wise- 
ly in loading the engine with only six or seven pounds weight 
on each square inch of the piston." 



50 JAMES WATT. 

Watt therefore found the engine involved in this dilemma ; 
either much or little condensation water was to be used. If 
much were used, the vacuum would be perfect, but then the 
cylinder would be cooled, and would entail an extensive waste 
of fuel in heating it again. If little were used, a vapour would 
remain, which would resist the descent of the piston, and rob 
the atmosphere of a part of its power. 

From the small quantity of water in the form of steam which 
filled the cylinder, and the large quantities of injected water to 
which this steam communicated heat, he was next led to inquire 
into the comparative density of steam and water, and what pro- 
portion of heat subsisted between them. Of these inquiries, 
Dr. Ure gives the following interesting account : — " In some 
conversations with which this great ornament and benefactor of 
his country honoured me a short period before his death, he 
described, with delightful naviete, the simple and decisive expe- 
riments by which he discovered the latent heat of steam. His 
means and leisure not then permitting an expensive and com- 
plex apparatus, he used apothecaries' phials ; with these he 
ascertained the two main facts, that a cubic inch of water would 
form about a cubic foot of ordinary steam ; and that the con- 
densation of that quantity of steam would heat six cubic inches 
of water from the atmospheric temperature to the boiling point. 
Hence he saw that six times the difference of temperature, or 
fully 800 degrees of heat had been employed in giving elasticity 
to steam ; and which must all be subtracted before a complete 
vacuum could be obtained under the piston of a steam engine. 
Struck with the singularity of this circumstance, " I mentioned 
it," says Watt, " to my friend, Dr. Black, who then explained 
to me his doctrine of latent heat, which he had taught for some 
time before this period (summer 1764) ; but having myself 
been occupied with pursuits of business, if I had heard of it, I 
had not attended to it, when I thus stumbled upon one of the 
material facts upon which that beautiful theory is founded." 

On reflecting further, it appeared to him, that in order to 
obtain the greatest power from the steam, the cylinder should 



JAMES WATT. 51 

always be kept as hot as the steam which entered it ; and that 
when the steam was condensed, the water of condensation and 
the water of injection should be cooled to 100 degrees of Fah- 
renheit, or lower if possible. 

Watt now gave his whole mind to the consideration of a 
method of " condensing the steam without cooling the cylinder." 
Various were the means contemplated by him to effect this 
object, when early in the year 1765, the thought struck him, 
" that if a communication were opened between a cylinder con- 
taining steam, and another vessel which was exhausted of 
air and other fluids, the steam, as an expansible fluid, would 
immediately rush into the empty vessel, and continue to do so 
until it had established an equilibrium ; and if that vessel 
were kept very cool, by some injection or otherwise, more steam 
would continue to enter until the whole was condensed" 

This happy conception was the first step in that brilliant 
career which has immortalized the name of Watt, and has 
spread his fame to the very skirts of civilization. But a diffi- 
culty presented itself. How were the injection water and the 
air entering with it, and also that produced by the condensation 
of the steam to be disposed of ? The water indeed could be 
allowed to run off through a syphon, but the air was not re- 
moved. At last it occurred to him that a pump would draw 
off both air and water, and preserve a perfect vacuum in the 
condenser. It was easy to see how this pump could be work- 
ed by the machine itself. This constituted the second great 
step in the invention. 

The piston had always heretofore been kept air-tight by water 
above it. Watt perceived, that in this new method, if any of 
the water entered the partially exhausted cylinder, which was 
now kept at a heat of 212°, it would boil, and by generating 
vapour, prevent the production of a vacuum, besides cooling 
the cylinder by its evaporation during the descent of the piston. 
To obviate this, he proposed to " lubricate the sides and keep 
the piston air-tight by employing wax or tallow." 

It next occurred to Watt, that the mouth of the cylinder being 



52 . JAMES WATT. 

open, the air which entered to act on the piston would cool the 
cylinder and condense some steam on again filling it. He 
therefore proposed " to put an air-tight cover on the cylinder, 
with a hole and shutting box for the piston to slide through, and 
to admit steam above the piston, to act upon it instead of the 
atmosphere." 

This was the third step in this great invention, and one which 
totally changed the character of the machine. It now became 
really a steam-engine ; for the pressure above the piston was the 
elastic force of steam, and the vacuum below it was produced 
by the condensation of steam ; so that steam was used both 
directly and indirectly as the moving power ; whereas, hitherto 
atmospheric pressure had been the moving power — steam hav- 
ing been used merely as a means of producing a vacuum. — 
Another source of the loss of heat — the cooling of the cylinder 
externally, by the air of the atmosphere — he at first proposed 
to remedy, by casing the cylinder in wood or some other sub- 
stance, which would conduct heat slowly ; but subsequently, 
he enclosed one cylinder within another, leaving a space be- 
tween them, which he kept constantly filled with steam. Thus 
the inner cylinder was kept constantly at the temperature of 
the steam which surrounded it. When once the idea of sepa- 
rate condensation struck him, all these improvements he states 
" followed in quick succession ; so that in the course of one or 
two days, his invention was so complete that he proceeded to 
submit it to the test of experiment." 

His experiments were made at first with a small apparatus, 
and finally with a working model having a nine inch cylinder. 
The results were most satisfactory. He saw that he had dis- 
covered a remedy for .the defects of the atmospheric engine. 
The steam was no longer wasted, and a more perfect vacuum 
was produced. He had computed that the heat wasted was 
three times greater than that usefully employed ; and as, by his 
improvements, nearly all waste was prevented, he contemplated 
and afterwards actually effected a saving of three-fourths of 
the fuel. 



JAMES WATT. — SPECIFICATION. 53 

Although fully sensible of the value of his discovery, 
he proceeded no further in it at this time, but "devoted 
himself, for upwards of three years longer, to pursuits far be- 
neath the powers of his mind." Indifferent health, the press 
of business, or the want of funds, prevented him from securing 
his invention by patent ; and at no period of his life was he 
possessed of the self-confidence necessary to bring his dis- 
coveries before those whose patronage or assistance might 
enable him to carry his designs into execution. 

On the occasion of his marriage, in 1764, he had left his 
apartments in the College, and commenced the practice of 
land-surveying, by the advice and with the occasional assist- 
ance of his uncle. He soon got into respectable practice ; 
and, in the course of his employment, he formed an acquaint- 
ance with Dr. Roebuck, an English gentleman, the founder of 
the celebrated Carron iron-works. Possessed of liberal educa- 
tion, considerable scientific attainments, unbounded enterprize, 
and some fortune, here was a man well qualified to appreciate 
the merit of Watt's improvement ; and by his assistance, Watt 
was enabled to erect an experimental engine, which was tried 
at a coal-mine, at Kinneil. This engine had an eighteen 
inch cylinder, and was successively altered and improved till 
it was brought to considerable perfection. During its erection, 
Watt, in connection with Roebuck, applied for his first patent, 
which was enrolled in April, 1769, and was for his "Methods 
of lessening the consumption of Steam, and, consequently, of 
Fuel, in his Fire Engine." The specification was not illus- 
trated with figures. It runs thus : 

" First. That vessel in which the powers of steam are to be 
employed to work the engine, which is called the cylinder in 
common fire-engines, and which I call the steam vessel, must, 
during the whole time the engine is at work, be kept as hot as 
the steam that enters it ; first, by enclosing it in a case of wood, 
or any other materials that transmit heat slowly ; secondly, 
by surrounding it with steam, or other heated bodies ; and 
thirdly, by suffering neither water, nor any other substance 



54 JAMES WATT. SPECIFICATION. 

colder than steam, to enter or touch it during that time. 
Secondly ; in engines that are to be worked wholly or partially 
by condensation of steam, the steam is to be condensed in 
vessels distinct from the steam-vessels or cylinders, although 
occasionally communicating with them : these vessels I call 
condensers ; and whilst the engines are working, these con- 
densers ought at least to be kept as cold as the air in the 
engines, by the application of water or other cold bodies. 
Thirdly ; whatever air or other elastic vapour is not condensed 
by the cold of the condenser, and may impede the working of 
the engine, is to be drawn out of the steam-vessels or con- 
densers by means of pumps, wrought by the engines them- 
selves or otherwise. Fourthly; I intend, in many cases, to 
employ the expansive force (pressure) of steam to press on the 
pistons, or whatever may be used instead of them, in the same 
manner as the pressure of the atmosphere is now employed in 
common fire-engines. In cases where cold water cannot be 
had in plenty, the engines may be wrought with this force of 
steam only, by discharging the steam into the open air as soon 
as it has done its office. Fifthly ; where motions round an 
axis are required, I make the steam-vessels in form of hollow 
rings or circular channels, with proper inlets and outlets for the 
steam, mounted on horizontal axles, like the wheels of a 
water-mill ; within them are placed a number of valves that 
suffer any body to go round the channel in one direction only. 
In these steam-vessels are placed weights so fitted to them as 
entirely to fill up a part or portion of their channels, yet ren- 
dered capable of moving freely in them by the means herein- 
after mentioned or specified. 

" When the steam is admitted in these engines between these 
weights and the valves, it acts equally on both, so as to raise 
the weight to one side of the wheel, and by the reaction on the 
valves successively, to give a circular motion to the wheel, the 
valves opening in the direction in which the weights are pressed, 
but not in the contrary ; as the steam vessel moves round, it is 
supplied with steam from the boiler ; and that which has per- 



JAMES WATT. 55 

formed its office may either be discharged by means of con- 
densers or into the open air. Sixthly, I intend in some places 
to apply a degree of cold not capable of reducing the steam to 
water, but of contracting it considerably, so that the engines 
shall be worked by the alternate expansion and contraction of 
the steam. Lastly, instead of using water to render the piston 
and other parts of the engines air and steam tight, I employ 
oils, wax, resinous bodies, fat of animals, quicksilver and other 
metals, in their fluid state. 

"Be it remembered, that the said James Watt does not 
intend that any thing in the fourth article shall be understood 
to extend to any engine where the water to be raised enters the 
steam vessel itself, or any vessel having an open communica- 
tion with it." 

After erecting the engine at Kinneil, Watt had begun to 
make arrangements to manufacture his engines on a consider- 
able scale, when his partner, Roebuck, became involved in 
embarrassments by the failure of some mining speculations, so 
as to be unable to make the necessary pecuniary advances. 
Harassed and disappointed, Watt was about to relinquish the 
further prosecution of his plans, when Mr. Bolton, a gentleman 
who had established a factory at Birmingham, made proposals 
to purchase Dr. Roebuck's share in the patent, which were 
accepted by that gentleman ; and, in 1773, Watt entered into 
partnership with Bolton. 

Watt now removed to Birmingham, and a brighter prospect 
opened ; his new colleague was a man of affluence, and of 
great personal influence, " and to a most generous and ardent 
mind, he added an uncommon spirit for undertaking what was 
great and difficult." " Mr. Watt," continues Professor Play- 
fair, " was studious and reserved, keeping aloof from the world ; 
while Mr. Bolton was a man of address, delighting in society, 
active, and mixing with people of all ranks with great freedom, 
and without ceremony. Had Mr. Watt searched all Europe, 
he could not have found another person fitted to bring his in- 
vention before the public in a manner worthy of its merit and 



56 JAMES WATT. 

importance ; and although of most opposite habits, it fortunately 
so happened that no two men ever more cordially agreed in 
their intercourse with each other." Finding that the period of 
the patent must expire before they could be reimbursed, even 
the necessary expenses attending the arrangements for manu- 
facturing the engines, with the advice and influence of his 
friends, application was made to Parliament for an extension of 
the term, which, after some opposition, was granted for twenty- 
five years from the date of his application (1775), so that his 
exclusive privilege should expire in 1800. An engine was now 
erected as a specimen for the examination of mining specula- 
tors, and the engines began to come into demand. The prin- 
ciple adopted by Watt, in granting licenses to use his engines, 
is remarkable for its fairness and liberality. It was, that he 
should receive one-third part of the saving of coals, which was 
made by his engines, when compared with the atmospheric 
engines hitherto used. 

Notwithstanding the manifest superiority of these engines 
over the old atmospheric engines, yet such was the influence of 
prejudice, and the dislike of what is new, that Watt found 
great difficulties in getting them into general use. The increased 
first cost also operated against them. In order to induce pro- 
prietors of mines who were unable or unwilling to be at the 
expense of new engines, Bolton and Watt at first took the old 
atmospheric engines in part payment, at a price far above their 
real value, and gave credit for the remainder until advantage 
should be experienced ; and they even erected some engines, on 
and at their own expense, to be paid provided they answered 
the expectations which they, as manufacturers, held out were 
obtained by their adoption. And it appears that they actually 
expended the sum of forty-three thousand pounds before they 
began to receive any remuneration. 

In the course of Watt's experiments, even before he procured 
his patent, he had been struck with the remarkable fact of what 
is now called the expansion of steam when admitted into a 
vacuum. This power was first partially adopted by him to 



JAMES WATT. 57 

equalize the motion of the piston, by shutting off the steam 
when the piston had gone through one-third of its stroke, 
leaving the other two-thirds to be completed by the expansive 
force alone. It was subsequently introduced as a means of 
saving steam in an engine at Soho manufactory, in 1776, and 
in 1778, at Shadwell Water Works ; and afterwards particu- 
larly described in his specification of a patent, in 1782. 

In both the atmospheric engine and the improved steam 
engine of Watt, the power of the steam acted only during the 
descent of the piston ; but during the ascent its agency was 
suspended. Besides this, the weights or counterpoises, which 
caused the ascent of the piston, acted against the power in the 
descent. Again, being of an intermitting nature, the power 
acted only in one direction. When applied merely to pumping, 
this suspension of impulse was no defect ; but when it was 
required to move machinery, it was a great drawback on its 
usefulness. Watt's next step towards the perfection of the 
machine was to obviate this inconvenience, and he accomplish- 
ed it by a very slight extension of his first idea. He had intro- 
duced steam acting against a piston to force it downwards ; he 
now formed a communication between both sides of the piston 
and the boiler, and also with the condenser, and made the steam 
act to press the piston upwards as well as downwards. This 
improvement constituted what is called the double acting steam 
engine ; and the mechanism was now, as far as the principle 
went, perfect ; and it was freed, for the first time, from the enor- 
mous dead weight of counterpoise. 

Even after the motion of the piston was equalized by shutting 
off the steam sooner or later from the cylinder, another source 
of irregularity presented itself in the varying quantity of steam, 
which in different states of the fire was admitted into the cylin- 
ders. To adjust this by means of the throttle valve, and to 
make this valve a self-acting one by the application of the 
governor, was the next successful effort of Watt's surprising 
ingenuity. 

It will be seen that Watt's specification contains the first 



58 JAMES WATT. 

idea of a rotary steam engine ; but the steam wheel not answer- 
ing, he directed, his attention to converting the reciprocating 
motion into a rotary. The contrivances of Hulls and Fitzgerald 
for this purpose have been already described. Patents for 
similiar ones had been taken out by Stewart, in 1769, and Wash- 
borough, in 1778. " Among the many schemes," says Watt, 
" which passed through my mind, none appeared so likely to 
answer the purpose as the application of a crank in the manner 
of a common turning lathe (an invention of great merit), of 
which the humble inventor, and even its era are unknown." 

On trial, it succeeded beyond his most sanguine expectations ; 
but being communicated to Washborough by the workman em- 
ployed to make the model, he forestalled the invention by taking 
out a patent in 1781, under the name of Steed. The fact was 
acknowledged by both the workman and Washborough's chief 
engineer ; the latter, however, excused himself by saying, that the 
same idea had occurred to him, and that he had even made a mo- 
del previously. " This," Watt says with great candour, " might 
be a fact, as the application of it to a single crank was suffi- 
ciently obvious ; and, in these circumstances, I thought it better 
to accomplish the same end by other means, than to enter into 
litigation, and by demolishing the patent, to lay the matter open 
to everybody." Accordingly, Ave find him procuring a patent 
for five different methods of producing rotary motion, among 
which was the sun and planet wheel motion, which he used 
until the expiration of Steed's patent, when the crank was 
resumed. In 1782, he obtained another patent for five different 
methods of applying steam. 

First, for an expansive steam engine, with six different con- 
trivances for equalizing the power ; secondly, the double power 
steam engine, in which the steam is alternately applied to press 
on each side of the piston, while a vacuum is formed on the 
other ; thirdly, a new compound engine, or method of connect- 
ing together the cylinders and condensers of two or more dis- 
tinct engines, so as to make the steam, which had been employed 
to press on the'piston of the first, act expansively upon the piston 



JAMES WATT. 59 

of the second, &c. ; and thus derive an additional power to act 
either alternately or conjointly with that of the first cylinder ; 
fourthly, the application of toothed racks and sectors to the end 
of the piston or pump rods, and to the arches of the working 
beams instead of chains ; fifthly, a new reciprocating semi- 
rotative engine or steam wheel. 

His next invention was the parallel motion, of which it may 
truly be said that it is difficult to find any contrivance more 
scientifically beautiful. This he secured by patent, in 1784 
and in the following year, he obtained a patent for a new smoke 
consuming furnace for the governor, steam guage, condenser 
guage, and indicator ; these completed the mechanism of the 
double engine. 

The expansive power of steam was investigated by Watt on 
scientific principles, and he explained his theory with great 
clearness. In the latter part of his life, he devoted a consider- 
able portion of his time and attention to the study of chemistry 
and its application to the arts. He wrote some historical notices 
of his own inventions, and corrected a few misstatements in Robi- 
son's article on steam, in his " Mechanical Philosophy," and 
added some notes, in which he gives an account of his experi- 
ments on latent heat and the elastic force of steam. 

We have already noticed the important services of Bolton in 
the introduction and advancement of the steam engine, and on 
reverting to the subject, find we cannot conclude this part of 
our sketch better than by quoting the Baron Dupin. " Watt's 
engine was, when invented by him, but an ingenious specula- 
tion, when Bolton, with as much courage as foresight, dedicated 
his whole fortune to its success. Men who devote themselves 
entirely to the improvement of industry, will feel in all their 
force the services that Bolton has rendered to the arts and me- 
chanical sciences, by freeing the genius of Watt from a crowd 
of extraneous difficulties, which would have consumed those 
days that were far better devoted to the improvement of the 
useful arts. 

In a memoir published at Basle, in 1769, T, H. Zigler de- 



60 



HORNBLOWER. 



scribes a curious apparatus, invented by him for trying the elastic 
force of different vapours, and gives the result of his experi- 
ments ; but they are unfortunately useless, from his having 
neglected to free his apparatus from atmospheric air. 

In 1781, Jonathan Hornblower, of Penrhyn, Cornwall, ob- 
tained a patent for a very peculiar and ingenious method of 
applying steam power. It consisted in having two cylinders, 
so connected together, that the steam, after acting in the first 
cylinder the same as in a high pressure engine, was permitted 
to expand itself in the other and operate a second time, and 
from thence it passed to a separate condensing vessel ; for if a 
partial vacuum be formed on one side of a piston while steam 
is confined on the other, the steam will expand and move the 
piston till an equilibrium of force is obtained, and the power 
communicated during this motion is an addition to the ordinary 
pressure. 

The effect of this arrangement would be similar to that pro- 
duced by Watt's plan of cutting off the steam before the piston 
has completed its stroke ; but the operation would be more 
equable, and as strong steam can be employed with less risk 
in a small than in a large cylinder, this mode of construction 
would be of decided advantage in large engines ; it is, however, 
difficult to make the two cylinders act in such harmony that one 
of them shall not retard the other. 

The action of the valves and pumps did not differ in principle 
from that of Bolton and Watt's engines, and the mode of con- 
densation in a separate vessel being clearly an infringement of 
the patent, Hornblower could make no use of his invention. 
Two very ingenious contrivances to obtain rotary motion by 
the direct action of steam were also patented by Hornblower, 
in the years 1798 and 1805 respectively. The first was ex- 
ceedingly complicated, but the second is pronounced by Tred- 
gold to be one of the simplest combinations ever proposed for 
that purpose. We copy his description. 

It consists of four vanes revolving in a cylinder around its 
axis. The vanes are like those of a smoke-jack, but of thick- 



MARQUIS DE JOUFFRAI . 61 

ness sufficient to form a groove in their edges, to hold stuffing, 
for the purpose of making them steam-tight in their action. 
They are mounted on an arbour, which has a hollow nave in the 
middle. Into this nave the tails of the vanes are inserted, and 
each opposite vane affected alike by having a firm connection 
with one another ; so that if the angle of one of the vanes with 
the arbour be altered, the opposite one will be altered also, and 
the opposite ones are set at right angles to each other ; so that 
when a vane is flatly opposed to the steam, the opposite vane 
will present its edge to it, and thus they are continually doing 
in their rotation on their common arbour ; so that the steam 
acts against the vane on its face for about a quarter of a circle, 
or ninety degrees, in the cylinder where it is destined to act ; 
and as soon as it has gone through the quarter of the circle, it 
instantly turns its edge to the steam, while at the same instant 
another vane has entered the working part of the revolution, 
and the rotation proceeds without interruption. This engine 
was to be furnished with the condenser and discharging pump 
of Watt, but Hornblower added what he considered an im- 
proved method of discharging the air from the condenser." 

A series of experiments on the elastic force of steam from 
32 to 212, and on the vapor of alcohol, were made by M. 
Achard, and published in 1782. He took notice that the tem- 
perature of alcoholic vapor is about thirty-five degrees lower 
than that of steam, when the elastic force of the two vapours 
is equal, but that the difference of temperature is not constant ; 
it seems to vary as the elastic force is greater or less. 

It does not appear that Jonathan Hulls ever subjected his plans 
for steam navigation to actual experiment. The first practical ap- 
plication of the steam engine to that purpose seems to have been 
by a French Nobleman, the Marquis de Jouffray, in 1781, when 
he made some experiments, on the river Soane, at Lyons, with 
a boat 140 feet long, 15 feet wide, and having a draught of 3.2 
feet. The boat is said to have been in use fifteen months. We 
are ignorant of the details and arrangement of the mechanism 
of this vessel, and equally so of the circumstance which occa- 
sioned the scheme to be abandoned. 



62 .viLLIAM SYMINGTON. 

A Mr. William Symington, of Falkirk, having made a model 
for a steam carriage of his invention, it was seen by Mr. Miller, 
of Dalswinton. This gentleman had for some time contem- 
plated the possibility of employing steam for propelling boats, 
and he engaged Mr. Symington to make a small engine to 
propel a double boat on Dalswinton Loch. The engine was 
made, fitted to the boat, and tried, on the loch, in the autumn of 
1788, and worked so well, that Mr. Miller determined on repeat- 
ing the experiment on a larger scale. Accordingly, he commis- # 
sioned Mr. Symington to purchase a gabart or large boat, at 
Carron, and to fit up another engine for the purpose. In the 
summer of 1789, the trial of his second boat was made, on the 
Forth and Clyde canal, having on board Messrs. Miller, Stanton, 
Taylor, and other persons ; but Mr. Miller, having shewn the 
practicability of his idea, from some unknown cause or other, 
appears to have relinquished the subject entirely afterwards. 

About this time, the Chevalier Bettancourt entered on a 
course of experiments on the force of the vapours of water and 
alcohol, at different temperatures. They were not sufficiently 
precise to develope the laws of vapour ; but they were more 
accurate than any which had been before published. Being 
employed by the Spanish Government to collect models of the 
best Hydraulic Machines, he made a model of the double- 
acting engine, with a new mode of forming the valves of his 
own invention, which model, according to Proney, was made 
from merely seeing the exterior of a double-acting engine when 
at work. 

The most extensive treatise on the steam engine, in the French 
language, is that of M. Proney, in his Architecture Hydraulique. 
The reader will be able to form a tolerable idea of the nature 
and merit of the work from the following description, which 
we have taken from Tredgold : 

" M. Proney begins with the properties of caloric, and the 
tables of Bettancourt on the force of vapour ; and from the lat- 
ter, constructs an empirical formula for calculating the force of 
vapour at different temperatures. These are not a little com- 



JOHN BANKS. 63 

plex, considering their want of conformity with experiment. 
He then proceeds to the description of engines as then con- 
structed, and their parts, which are illustrated by plates, having 
figures on a large scale. When he arrives at the parallel mo- 
tion, the nature of the curve described by the extremity of the 
piston rod is very fully investigated with tables, to shew its 
variation from a straight line for a given range in the curve. It 
is followed by the proposal of a method for determining the 
diameter of the steam-cylinder, which is little better than tell- 
ing the artist to guess at it, and correct his guess by an intri- 
cate formula. The part on the steam engine terminates with 
a calculation of the effect produced by a given quantity of fuel, 
where the time of combustion is certainly erroneously intro- 
duced. 

His formulae for the expansive forces of elastic fluids and 
vapours, at different temperatures, have been shewn to be 
based on inaccurate experiments, and are, consequently, wholly 
useless. 

In 1795, a work on mill-machinery appeared, by Mr. John 
Banks, in which he treats of the maximum of useful effect 
in Atmospheric Engines. His investigation differs from those 
of Blake and Emerson, in his considering the space or length 
of the stroke the given quantity ; and his solution is incorrect, 
owing to his considering the pressure of the atmosphere merely 
as a gravitating weight. In his solutions, he includes the weight 
of the moving parts of the engine, and he adds some practical 
formulas, with examples for the statical equilibrium of ma- 
chines employed to raise water. In a subsequent publication, 
he treats on the strength of engine beams, and gives a descrip- 
tion of a rarefaction-guage for cylinders and condensers. His 
rules for the strength of beams are, to find the relation between 
the pressure and breaking weight, and to let the weight exceed 
the pressure by six, eight, or ten times. These rules apply to 
both wood and iron. The principle of his guage is that of the 
barometer, but differs from the common condenser-guage in 
having a cistern for the mercury instead of a syphon. 



64 



EDWARD CAItTWRIGHT. 



In 1797, the Reverend Edward Cartwright, a gentleman well 
known for other mechanical inventions, obtained a patent for the 
construction of a single-acting engine, which is represented in 
figure 15. 

A is the cylinder ; B, the piston ; I, the pipe which conducts 
the steam to C, the condenser, where it passes between the 
inner and outer cylinder into the pump D, which returns the 
condensed fluid back into the boiler, through E, the air-box, 
with e, its valve. As the pipe from the pump, through which 
the condensed fluid is returned into the boiler, passes through 
the air-box, what air or elastic vapour may be mixed with the 
fluid rises in the box till the ball that keeps the valve e shut 
falls and suffers it to escape. F is the steam-valve ; a, the 
piston-valve; H H, two cranks, upon whose axles are two 
Fig. XV. 




EDWARD CARTWRIGHT. 65 

equal wheels working in each other, for the purpose of giving a 
rectilinear direction to the piston-rod ; and M is the cistern 
that contains the condensing water. O is the fly-wheel, for 
regulating the motion. 

This simple but ingenuous and elegant machine merits our at- 
tention on more grounds than one. First, the steam is con- 
densed, without, a jet, by the application of cold water to the 
outside of the condenser. To effect this, two cylinders are 
placed one within the other ; the water of the cold cistern flow- 
ing through the inner cylinder and surrounding the outer one. 
The narrow space between the two cylinders forms the con- 
denser, and thus a very thin body of steam is exposed to a large 
cooling service. Second, the communication between the cylin- 
der and condenser is constantly open, so that the condensation is 
continuous, whether the piston be ascending or descending. 
Third, the piston, instead of being packed in the ordinary 
way, was made solely of metal, and so constructed as to be ex- 
pansive. It consisted of two plates, between which metallic 
rings, cut into segments, were placed ; these rings being forced 
outwardly against the surface of the cylinder by springs, the 
piston adapts itself to any inequality which may arise in its 
form, and fits it more accurately the longer it is w r orked, so that 
the machine improves as it wears. The piston-rod works in a 
metallic box, constructed in a similar manner. Fourth, three 
valves only are employed — two in the cylinder for the admis- 
sion and emission of steam, and one to allow the escape of air 
from the air-box, and these are as nearly self-acting as can well 
be conceived. 

A chief object with Cartwright, in this arrangement, was the 
substitution of the vapour of ardent spirits for that of w T ater to 
work the engine. Alcohol boils at lower heats than water, and 
it was then supposed that a sufficient power might be obtained 
from it with a saving of half the fuel. Now, one of the pecu- 
liarities of this mode of construction is, that the liquid used to 
produce the steam circulates through the machine without ad- 
mixture with any other fluid, and with little or no waste ; so 
9 



66 JOHN CURR. 

that the boiler requires no more feeding than can be supplied 
from the air-box. Under these circumstances, the use of alcohol 
would be attended with no expense after the first supply. He 
further suggested that the engine might be used as a still, as 
well as a mechanical power, in which case the whole of the 
fuel would be saved ; but how this was to be done, has not 
been explained. 

Though both theory and practice join to assure us that this 
engine cannot be advantageously employed, we are struck with 
admiration at the elegant ingenuity which distinguishes the de- 
sign. The highest constructive ability — that- of simplicity — is 
displayed throughout ^.the whole ; and we must not omit to ob- 
serve that, to Cartwright we are most undoubtedly indebted 
for the invention of the metallic piston ; the other parts of his 
machine were only new in their adaptation and arrangement, 
but this was entirely new in principle, and has proved as prac- 
tically useful as the idea was theoretically beautiful. 

A contrivance for a rotary machine is included in the same 
patent ; but independently of the loss of effect necessarily at- 
tendant on the action of steam on a rotary piston, its construc- 
tion, though apparently simple, is, in reality, involved in 
difficulties. 

A work on the Atmospheric Engine was published at Shef- 
field, in 1797, by John Curr, illustrated by plates, showing the 
parts of engines, on a large scale. It treats on the proportions 
of the parts, and gives general directions for their construction, 
in brief technical terms ; but it contains no general description 
of the engine, and no reasons are assigned for any of the pro- 
portions ; but, in treating of the pressure on the piston, he 
says, that when the pressure was increased from " seven to eight 
and a half lbs. per square inch, the engine did less, and also 
when reduced to 6.1 lbs. it did somewhat less ;" and he does not 
recommend a greater load than six and a quarter or'six and a 
half lbs. The engine had a sixty-one inch cylinder, and made 
twelve strokes, of eight feet and a half inch, per minute. The 
consumption of coals was ten hundred weight of small coal, or 



KIER. NUNCARROW. MURRAY. 67 

slack, per hour. The power of the engine would be nearly 
equal to fifty-four horses' power ; and as the ratio of coal to 
slack is about as three to four, it is equivalent to about 840 
lbs. of coal per hour: and, at this ratio, 1 lb. of slack raises 
97,000 lbs. of water one foot high, and 1 lb. of coals, 130,000 
lbs. one foot high. 

In Nicholson's Philosophical Journal for 1797, we find a de- 
scription of an engine, erected in 1793, by a Mr. Kier. It was 
on Savery's principle, and acted wholly by condensation. 

"The steam-vessel being raised somewhat above the height 
to which the water was to be raised, it had a provision for 
letting in a small portion of air between the steam and the 
water, and the construction was exceedingly simple and judi- 
cious. The boiler was seven feet long, five feet deep, and five 
feet wide ; and it consumed six bushels (522 lbs.) of good 
coal in twelve hours, in its best state, and seven in its worst 
state. Under these circumstances, it made ten strokes per 
minute, and raised seventy cubic feet of water twenty feet high 
in a minute. According to this statement, in the best state of the 
engine, 87 lbs. of coal were consumed in two hours, or 120 
minutes, and 1,400 cubic feet of water raised one foot high per 
minute; or, 1,400X120=168,000 cubic feet by 87 lbs. of 
coal; which, multiplied by 62 \ lbs., the weight of a cubic 
foot of water, and divided by 87, gives 120,000 lbs. for the 
load, raised one foot by one lb. of coal ; which is about one 
half the effect produced by an engine with a piston and Watt'st 
condenser, and less than the effect of the common atmospheric 
engine as used for the coal mines." 

In this year, John Nuncarrow also proposed an improve- 
ment of Savery's engine, by adding a separate condenser, 
giving motion to a water-wheel by a fall obtained by the power 
of steam. His construction certainly appears to possess con- 
siderable advantages over the original, but at the same time 
presents difficulties which would effectually prevent its being 
carried into effect. 

Mr. Murray, of the firm, Fenton, Murray & Wood, of Leeds, 



68 MURRAY. 

did much in improving many parts of the steam engine, and ob- 
tained several patents for his improvements. Some of his 
methods, it appears, had been previously made use of by Bol- 
ton and Watt, but till Murray took out his patents, they were 
not publicly recorded. In his first patent (1799) for "saving 
Fuel and lessening the expense of Engines," " he proposed to 
place a small cylinder, with a piston on the top of the boiler, 
connected to a rack, by means of which the force of steam 
within the boiler opens or closes the damper fixed on an axis in 
the chimney ; thus increasing or decreasing the draught of the 
fires, so as to keep up a regular degree of elastic force in the 
steam. Mr. Murray also thought some advantage would be gained 
by placing the steam cylinder in a horizontal instead of a verti- 
cal position, with a view of rendering the engine more compact 
than the usual construction. He also adopted a new method of 
converting the reciprocating motion of the piston to a rotary 
one of equal power, by means of the property of the rolling 
circle, and showed how to fix the wheels for producing motion 
alternately, in perpendicular and horizontal directions. His 
next patent, taken out in 1801, was for six different objects. 

First, for a method of constructing the air-pump ; second, 
for a method of packing stuffing-boxes, &c, by bringing 
the moveable parts of each in immediate contact, which 
prevent the piston-rod receiving any oblique pressure, by 
the lid being screwed down more on one side than the other. 
^The third and fourth methods relate to the construction and 
motion of the valves. The fifth was a method of connecting the 
piston-rod to the parallel motion ; and the last, for the con- 
struction of fire-places, by which the smoke arising from the 
fire was to be consumed. In most of these, however, he had 
been anticipated in practice. 

In 1802, he obtained a third patent for a portable engine, 
which patent, however, was repealed in the following year, at 
the instance of Bolton and Watt, as it included some of their 
methods. Bolton and Watt's portable engine was first con- 
structed in 1806. 



MURDOCH. — DR. ROBISON. 69 

Mr. Murdock, of Redruth, Cornwall, partner in the firm of 
Bolton and Watt, and well known as the inventor of gas-light- 
ing, made several important improvements in constructing cyl- 
inders and working the valves. His patent was taken out in 
1799. These improvements consist of a more equable mode of 
boring the cylinders and pumps, by means of an endless screw 
and toothed-wheel. 

" Casting the steam-cases of one entire piece, to which the 
cover and bottom of the working cylinder are to be attached." 
He also proposed to cast the cylinder and steam-case in one 
piece, of considerable thickness, and bore a cylinder interstice 
between the steam-case and steam-vessel, leaving the two cyl- 
inders attached at one end, and to close the other by a ring of 
metal. Another improvement included in the patent was, a plan 
for simplifying the construction of the steam-valves, or regula- 
tors, of the double engine, by connecting together the upper 
and lower valves, so as to work with one rod or spindle. The 
tube which connects them, being hollow, serves as an eduction 
pipe to the upper end of the cylinder, and a saving of two 
valves is effected ; and lastly, he adds a scheme for a rotary 
engine, consisting of two toothed-wheels, working in an air- 
tight vessel, which, he imagined, would work with considerable 
power. 

The successful application of the steam engine to draining the 
Cornish Mines was greatly creditable to the skillful superintend- 
ence, the activity, and the integrity of Murdock, and the resources 
he displayed in overcoming the various difficulties which pre- 
sented themselves. Many of the perfections of the double en- 
gine are the result of his contrivances ; in particular, his mode 
of opening the valves added much to its neatness and simplicity. 

Amongst those who have written on the principles and con- 
struction of the steam engine, Dr. John Robison possessed the 
rare quality of being able judiciously to combine theoretical and 
practical information, joined to a facility and clearness of ex- 
pression, which renders his work invaluable to the inquirer. 
He bestowed much attention on the subject, and his close inti- 



70 DR. ROBISON. 

macy with so liberal a friend of science as Watt, gave him ac- 
cess to a quantity of data which he w r as able to make use of 
to the best advantage. He commences with an article on the 
physical properties of steam, in which the phenomena of boil- 
ing, and the effect of pressure in altering the temperature ne- 
cessary to produce that action, with the popular doctrine of 
latent heat, are fully, though rather diffusely, stated. A series 
of experiments on the elastic force of the steam of water and the 
vapour of alcohol, are given ; but these, unfortunately, are not 
sufficiently accurate : and, in consequence, the rule for the 
elastic force of steam which he derives from them, and gives as 
" sufficiently exact for practical purposes," is far from being so, 
and its adoption has tended to mislead several engineers in their 
attempts at improving the engine. Independent of this, how- 
ever, the article is replete with useful information, and may be 
pronounced the best treatise on the power of steam which had 
at that time appeared. 

This article is followed by a historical account of the steam 
engine and its principal inventors, with detailed descriptions of 
their various engines, blended with much valuable theoretical 
discussion, though slightly open to the charge of wanting sys- 
tematic arrangement. His descriptions are full and particular, 
and must have been highly useful to all those who were at that 
time engaged in constructing the steam engine, or investigating 
its theory. In this portion of his work, some think that his 
personal feelings, as a friend of Watt, ioined to national preju- 
dices, have prevented him from treating the claims of Papin 
with sufficient respect; but in all other cases he may be pro- 
nounced strictly impartial. 

His general reputation and ability, as a writer on mixed me- 
chanical sciences, contributed much to the beneficial effects pro- 
duced by his articles on the steam engine ; and it was no small 
advantage to the practical man to have "the scattered knowledge 
on the subject collected with so much skill, and treated with so 
much clearness and good taste." 

Bossut's " Speculations on the best Velocity for Atmospheric 



MESSRS. ROBERTSON. BRAMAH. — PENWICK. 71 

Engines" were reprinted by Robison, with additions ; as also 
Watt's " Mode of Computing the Pressure on the Piston of the 
Expansive Engine." These works, however, are not calculated 
to be of much use to the mechanic. 

In 1800, the Messrs. Robertson, of Glasgow, contrived a new 
mode of building boiler fire-places. It is on the same principle 
as those constructed by Watt, but more convenient in practice. 
They also invented an apparatus for using the steam which 
escapes by the sides of the piston as part of the effective power ; 
but the complexity and expense was so great, compared with 
the small increase of power gained, as to render the contrivance 
of little use. 

In 1801, a patent was obtained by Joseph Bramah, for various 
improvements in construction ; the principal of which was a 
variation in the form, and a new mode of applying the four-way 
cock. The objection to this cock as commonly worked, was its 
inequality of wear, which allows the steam to escape, and causes 
a loss of power. Instead of turning it backwards and forwards 
in the usual way, Bramah made it to revolve continually in the 
same direction. The same effect is produced ; but this mode 
of action renders the wear of the cock more equable, and con- 
sequently adds much to its durability. 

He also adjusted the movements, so as to give, at the proper 
time, as instantaneous and free a passage to the cylinder and 
condenser as possible, and formed the apertures, so that the 
cone might be pressed equally into its seat by the force of the 
steam. 

In the same year, a Mr. Thomas Fenwick published a series 
of tables for the proportions of the cylinders of atmospheric 
engines to produce given effects. 

He infers from some experiments, that the whole friction of 
the atmospheric engine is about four pounds per square inch 
on the area of the piston ; and on account of the frequent bad 
effects attending designing an engine with too small an allow- 
ance for excess above its ordinary work, he makes his compu- 
tations at five and a half lbs. effective power for each square 
inch of piston. 



72 DUNDAS. DALTON. 

Having had considerable experience in the management of 
coal works near Newcastle, he had a good opportunity of know- 
ing what would best answer in practice. 

A later edition contains " tables for an improved atmospheric 
engine with a separate condenser, in which the ratio of the effect 
is as 17 ; 10, when the same sized cylinder is used." 

The saving of fuel at coal mines is not a matter of much im- 
portance, and therefore does not enter into his calculations. 
To a coal owner, an engine which is simple and efficient in its 
operations, and which can be erected at a moderate cost, is of 
more value than one which being of finer construction requires 
a greater outlay. 

Mr. William Symington, already mentioned, as having con- 
structed the engines for Miller's experiments on steam naviga- 
tion, had not altogether abandoned the project. Accordingly, 
having commenced business at Falkirk, we find him, in 1801, 
building another experimental steam boat, under the encourage- 
ment of Thomas Lord Dundas, of Kerse, who wished to intro- 
duce steam power on the Forth and Clyde Canal, in place of 
horse power. Experiments on a large scale were instituted at 
a cost of nearly $15,000, and in 1802, the boat was completed. 
It was a tow-boat, with a cylinder twenty-two inches in diame- 
ter, and a four feet stroke. It proved to be well adapted for the 
intended purpose ; but the use of it was interdicted by the Canal 
Company, from an idea that it destroyed the banks. A com- 
plete model of this boat, with a set of ice-breakers attached, is 
preserved in London, at the rooms of the Royal Institution. 

Whilst the investigation of the qualities of steam was con- 
fined to its use for mechanical purposes, few interested them- 
selves in the inquiry, and its progress was comparatively slow ; 
but as a knowledge of the nature and properties of that and 
other vapours became important in chemistry, meteorology, and 
other branches of natural philosophy, the subject obtained more 
extensive consideration, and engaged the attention of a different 
class of writers. Of these, Mr. John Dalton was the first 
chemist who attempted a full investigation of the theory of 



TREVITHICK AND VIVIAN. 73 

vapour. He distinguished himself by " an accurate series of 
experiments on the expansive force of steam at temperatures 
under 212°. He ascertained various phenomena, and made 
experiments relative to the expansion of gases, the mixture of 
air and vapour, and the nature of evaporation and combustion- 
He did not succeed in his attempts to reduce any of these to 
general laws ; but he gave such an impulse to the inquiry, as 
eventually to render it one of universal research among chemi- 
cal philosophers ; though owing to the prevailing idea that Watt 
had already exhausted the subject ; that his experiments and 
results had made us sufficiently acquainted with the power and 
nature of steam ; inquiry in this direction had been checked 
among men of science ; and, at first, the importance of Dalton's 
experiments, and even their connection with the theory of the 
steam engine, were little noticed. 

Although the use of steam of high pressure had been at- 
tentively considered and applied (to a working model at least) 
by Leupold — and had been the subject of applications for Patent 
Rights by Watt * and Matthew Murray — still, until this date 
(1801), it would appear that the idea of carrying out this simple 
and convenient mode of using steam as a motive power was 
reserved for the enterprize of two Cornish Engineers, Trevi- 
thick and Vivian. 

The small amount of capital possessed by many of the 
owners of mines, and the constant necessity of having some 
adequate power to free them from water, together with the high 
prices demanded for Bolton and Watt's pumping engines, con- 
spired to call the attention of these men to the necessity of pro- 
viding some more economical and equally useful combination 
for obtaining the same end. 

* It was generally understood, that although Mr. Watt patented the high 
pressure engine, it was not his intention that it should be employed except in 
eituations where condensing water could not be had. He considered the risk 
too great and life too valuable to be endangered for the saving in the mere 
original cost of the engine, there being none in the consumption of fuel. 

10 



74 ARTHUR WOLF, 

We may thus safely say, that the first useful application of 
high pressure steam is due to these two gentlemen. They 
were the first, also, who applied steam to produce loco- 
motion upon rail-roads, to which purpose they adapted their 
high pressure engines ; and, when used for this purpose, the 
boiler was composed of cast iron, of a cylindrical form, mounted 
horizontally upon a frame with four wheels, the cylinder 
of the engine being placed vertically within the boiler, 
near to one end. The piston-rod moved a cross-head between 
two guides ; and, by a connecting rod descending from each end 
of the cross-head to two cranks, the motion was communicated to 
the wheels of the carriage : a fly-wheel in this case is not requir- 
ed, because the momentum of the carriage supplies its place.* 

The first trial of this species of moving power for carriages 
took place on a rail- way at Merthyr Tydfil, in 1805. Its use 
was not at that period followed up, but it is now, with some 
improvements, used generally on all rail-roads. 

Watt's patent for his mode of condensation, and Hornblower's 
patent also, having expired, Mr. Wolf combined the two cylin- 
ders of the latter with the condensing apparatus of the former, 
only using steam of high pressure in the small cylinder. The 
mere fact, however, of using higher steam, was too poor a title 
for a patent; consequently, he claims the discovery of a new 
law of the expansibility of steam, which he put forth as the 
result of actual experiment. He must, however, have made 
some curious mistake either in his calculations, or in the appa- 
ratus by which his experiments were effected. He asserted 
that steam, of any number of pounds' pressure above the pres- 
sure of the atmosphere, would expand to an equal number of 
times its volume, and still be equal in elastic force to the 
pressure of the atmosphere, the temperature being unaltered ; 
hence, steam generated at forty pounds on the square inch, was 

* It is but justice to observe, that Mr. Murdock made his working model of 
a locomotive engine in 1782; and that, as Mr. Trevithick was a pupil of Mur- 
dock's, then in Cornwall, it is natural to suppose that he received many of his 
ideas of locomotion from that gentleman. 



OLIVER EVANS. 



75 



-expected to expand to forty times its own bulk, and yet be equal 
to the pressure of the atmosphere. But it is a well known law 
in the expansion of fluids, that the temperature being constant, 
the bulk is inversely as the pressure ; and, calling the pres- 
sure of the atmosphere 14 pounds, we have 14: 14 X 40: : 1 :4, 
nearly. Therefore, steam generated at 54 pounds on the square 
inch, or 40 pounds above the pressure of the atmosphere, 
would expand only to four, and not to forty times its volume. 
(See article on this subject.) 

Although Wolf's assertions were so directly opposed to the 
laws of the constitution of elastic fluids, they have found their 
way, as undoubted experimental truths, into works which ought 
to have high claims to respectability. 

In this year (1801), Oliver Evans applied to the Legislature of 
Pennsylvania for a patent for the "Application of High Elastic 
Steam, the great advantage of which," he says, "I had dis- 
covered, demonstrated, explained, and made known. I have 
dispensed with the heavy beam, condenser, and air pump, and 
simplified the construction of the boiler, cylinder, piston, and 
working gears : my plan requires a small forcing pump to sup- 
ply the boiler. Thus I have produced an engine ten times as 
powerful, more governable, and easier varied to suit any task 
assigned to it than that of Bolton and Watt : it can be con- 
structed at half the price, and will expend only one-third the 
fuel to do as much work as theirs." 

It would appear that his attention had been called to the use 
of high pressure steam, from the circumstance of hearing of its 
immense force as exhibited by a boy to a brother of his, by 
means of an old gun barrel ; of which, having stopped up the 
touch-hole, and having poured about a gill of water into it, he 
with a strong plug stopped up the muzzle, and then placing the 
breech in a smith's fire, after some time, the plug was driven 
out with a great crack. This circumstance occurred about the 
year 1772, whilst he was apprentice to a wheel- wright ; and 
as he had long been trying to find out some motive power for 
conveying goods along the roads other than animal or human 



76 OLIVER EVANS. 

power, the idea instantly struck him that here was the very 
thing he had sought so diligently. Soon after this occurrence, 
he met with some desc ip ion of the old atmospheric engine, 
and his imagination was forthwith at work, how to modify this 
arrangement, so as to use the power of steam without conden- 
sation. 

In the year 1786, he petitioned the Pennsylvania Legis- 
lature to grant him the exclusive right to use steam wagons in 
that State ; but without success. 

On the 21st of May, 1787, he obtained from the Legislature 
of Maryland an exclusive right to make and use steam wagons 
for the term of fourteen years, in that state ; but it would ap- 
pear that all his arguments were not sufficient to induce capi- 
talists to join him in the speculation, so the projects were con- 
sequently dropped. 

He now set to work and constructed an engine for a mill to 
grind plaister of Paris, which succeeded, and by which he could 
break and grind 300 bushels, or 12 tons, in twenty-four hours. 
The dimensions of this engine are as follows : the diameter 
of the cylinder six inches, and the length of stroke eighteen 
inches. The annexed wood cut represents the identical engine 
which he patented, and which turned the machinery in a shop 
at Philadelphia, where the writer worked ten years ago. 

We will again use Mr. Evans' own words in the following 
description of his first using steam to propel a carriage and 
move a boat : 

" In the year 1804, I constructed, at my works, situate a mile 
and a half from the water, by order of the Board of Health of 
the city of Philadelphia, a machine for cleaning docks. It con- 
sisted of a large flat or scow, with a steam engine of the 
power of five horses on board to work machinery, to raise the 
mud into flats. This was a fine opportunity to show the pub- 
lic that my engine could propel both land and water carriages, 
and I resolved to do it. When the work was finished, I put 
wheels under it (and though it was equal in weight to two 
hui.dred barrels of flour), and the wheels fixed with wooden 



EVANS' ENGINE. 




78 OLIVER EVANS. 

axletrees, for this temporary purpose, in a very rough manner,, 
and with great friction, of course ; yet, with this small engine, I 
transported my great burden to the Schuylkill with ease ; and 
when it was launched in the water, I fixed a paddle-wheel in 
the stern, and drove it down the Schuylkill to the Delaware, 
and up the Delaware to the city (14 or 15 miles), leaving all 
the vessels going up behind me, at least half way, the wind 
being ahead, and in the presence of thousands of spectators — 
a sight which I supposed would have convinced them of the 
practicability of both steam carriages and steam boats. But in 
this I was sadly disappointed ; for they made no allowance for 
the disproportion of the engine to its great load, nor for the 
temporary manner in which it was fixed, nor the great friction, 
ill form of the boat, &c, but supposed it was the utmost I 
could do." 

Mr. Evans here remarks — and with natural and excusable 
chagrin — at the same time casting a very just censure upon the 
want of energy and speculative spirit of the wealthy inhabitants 
of Philadelph _i : 

" Had I been patronised, as Mr. Fulton was by the State of 
New-York, with the exclusive right for thirty years, and by a 
Mr. Livingston with thirty thousand dollars, to make the ex- 
periment, I might have showed steam boats in full operation 
long before Mr. Fulton began his boat, which was finished 
in 1807, twenty years after I petitioned the Legislature of 
Pennsylvania, and three years after the above mentioned ex- 
periment." 

Mr. Evans entertained many ideas which, in his day, were 
thought almost evidences of insanity, but we see that his wild- 
est schemes either have already been or are now being carried 
into execution. Thus, locomotive engines are travelling at a 
rate of sixty miles an hour, and Perkins has raised the pressure 
of steam to a degree far exceeding the pressure or elasticity of 
ignited gunpowder. His, however, were not all speculative 
theories even in his own day, as the following will fully show : 

" The principles are now in practice, driving a saw-mill at 



OLIVER EVANS, 79 

Mauchack's, on the Mississippi ; two at Natchez, one of which 
is capable of sawing 5,000 feet of boards in twelve hours ; a 
mill at Pittsburgh, able to grind twenty bushels of grain per 
hour ; one at Marietta, of equal powers ; one at Lexington, 
Ky., of the same powers ; one, a paper-mill, of the same ; one 
of one-fourth the power, at Pittsburgh ; one at the same place 
of three and a half times the power, for the forge, and for roll- 
ing and splitting sheet iron ; one of the power of twenty-four 
horses, at Middletown, Conn., driving the machinery of a cloth 
manufactory ; two at Philadelphia, of five or six horses ; and 
many making for different purposes : the principle applying to- 
all purposes where power is wanted." 

We will now close our notice of this enthusiastic and inge- 
nious inventor with a few of his predictions in 1813 : 

1. "The time will come, when people will travel in stages 
moved by steam engines, from one city to another, almost as 
fast as birds fly — fifteen or twenty miles an hour. 

2. "A carriage will set out from Washington in the morning ; 
the passengers will breakfast at Baltimore, dine at Philadelphia, 
and sup at New-York the same day. 

"To accomplish this, two sets of rail-ways will be laid, trav- 
elled by night as well as by day, and the passengers will sleep 
in these stages as comfortably as they now do in steam stage 
boats. 

3. " A steam engine, consuming from a quarter to a half cord 
of wood, will drive a carriage 180 miles in twelve hours, with 
twenty or thirty passengers, and will not consume six gallons 
of water. 

4. " These engines will drive boats ten or twelve miles per 
hour, and there will be many hundred steam boats on the Mis- 
sissippi, * and other western waters, as prophesied thirty years 



* ?.Tr. Evans lived to know, that in 1813, there were three steam boats on 
the Mississippi ; and recent information gives the number as over 1,000 ves- 
sels; most of which have been built at Pittsburgh, Wheeling, and Cincinnati. 



80 OLIVER EVANS. 

" Posterity will not be able to discover why the legislature or 
Congress did not grant the inventor such protection as might 
have enabled him to put in operation these great improvements 
sooner, he having asked neither money, nor a monopoly of any 
existing thing. 5 ' 



PART II. 



PROPERTIES OF STEAM. 



ll 



CHAPTER I. 

PROPERTIES OF STEAM. 

First Cause. — Heat. — Effects. — Solids. — Liquids.— Gases. — 
Thermometer. — Table of Properties of Bodies. — Table of 
Expansion of Water by Heat. — Barometer. — Steam Guage. 
— Tables of Elastic Force of Steam. — Rules for Calculating 
the same. — Salt, or Sea Water. — Analysis. — Salinometer. 
— Motion of Steam. — Table of Motion. — Expressions of 
Force of Steam. — Rules for Calculating. — Velocity of 
Steam. — Bent Pipes. — Table of Properties of Steam. — 
Loss by Cooling. 

1 . The first subject of inquiry is that of heat, the agent used 
in the production of steam. 

2. The natural and perceptible effect of heat when applied to 
different substances tends, in some, to expand and dilate their 
bulk to the altering their form and appearance ; in others, en- 
tirely to dissolve and separate their component parts or atoms. 
Its action on metals is evidence of the former, and its operation 
on liquids an example of the latter process. 

3. Of the actual nature of heat we may be said to know 
nothing, further than what is evident to the senses, by its action 
on the body, or its visible effects on matter : it would be vain, 
therefore, to waste time in wild conjecture or idle speculation, 
when it is in our power to note its action upon substances pre- 
sented to its operation, and by this means establish such rules 
as may be useful in the following inquiries. 

4. On the application of heat, the expansion and contraction 
of solids are various as their respective nature or qualities ; but 



84 



PROPERTIES OF STEAM. 



the same material will expand and contract in all cases alike ; 
regard being had that the bulk and temperature are the same. 

5. The case, however, with liquids is widely different, hardly 
any two expanding alike, or even expanding in any equal degree, 
for an equal increase of heat at different temperatures. The 
expansion is less rapid, the nearer it approaches the point 
at which it congeals, and more rapid as it nears its boiling 
point. 

6. In elastic fluids the case is again different ; whether gases 
or vapours are subject to its action, a change of temperature 
causing an equal and uniform expansion, which expansion is the 
same in all. 

7. To the study and knowledge of the above well-established 
facts, does that beautiful and useful little instrument the ther- 
mometer, or heat measure, owe its existence ; but as its con- 
struction and use are now so generally understood, we may be 
spared the repetition of its description. 

8. To assist us further in our subject, we will here subjoin 
the result of many experiments made by those who have de- 
voted much time and ability towards their compilation, and on 
whose accuracy we may rely. 

TABLE I. — Containing some of the Properties of various 
Bodies. 









Expands in heat 






Melting 
and boil- 


Contracts in 


ing from 32 t< 


) Power of 


Names of bodies. 


cooling in parts 


212 deg. Fahren 


conduct- 




ing points 


of an inch lor ea. 


heit, the length 


ing heat. 






foot in length. 


being 1.00000. 




Cast iron melts . . 


17.977 c 


.124 


.00111 


1.2 


Wrought iron, ) 
welding hot ) 




12.780 


.137 


.00122 


1.1 


Copper melts . . 




4.587 


.193 


.00172 


1.0 


Brass melts . 






3.807 


.210 


.00187 


1.0 


Steel, red hot . 






1.077 


.133 


.00118 




Zinc melts . . 






700 


.329 


.00294 




Mercury boils 






660 




.01851 




Lead melts . . 






594 


.319 


.00286 


2.5 


Bismuth melts 






476 


.156 


.00139 




Tin melts . . 






442 


.278 


.00248 


1.7 


Water boils. . 






212 




.04002 





PROPERTIES OP STEAM. 



85 



10. Thus having some certain data with regard to solids, we 
here insert a table of the expansion of water by heat. 

TABLE II. — Showing the Expansion of Water by Heat. 



Temperature. 


Expansion. 


Temperature. 


Expansion. 


12° F. 


1.00236 


122° F. 


1.U1116 


22 


1.00090 


132 


1.01367 


32 


1.00022 


142 


1.01638 


42 


1. 


152 


1.01934 


52 


1.00021 


162 


1.02245 


62 


1.0C083 


172 


1.02575 


72 


1.00180 


182 


1.02916 


S2 


1.00312 


192 


1.03265 


92 


1.00477 


202 


1.03634 


102 


1.00672 


212 


1.04012 


112 


1.00880 







12. Before taking into consideration the elastic force of steam 
and the rules for calculating the same, it will be well to explain 
the means used for practically measuring it, and the reason for 
using such means. 

13. If a glass tube closed at one end, and rather more than 
30 inches long be filled with mercury, and then inverted into a 
vessel containing mercury, so that only about 28 inches of the 
tube may be above the surface of the mercury in the vessel, 
the mercury in the tube will remain suspended ; if the tube, 
however, be gradually raised in a vertical direction until more 
than 30 inches are above the level of the surface in the vessel, 
the mercury will descend in the tube until it shall be just 30 
inches above the level in the vessel. 

14. The mercury will not always, however, remain station- 
ary at 30 inches, but will vary its height according as the atmo- 
sphere is lighter or heavier; or according to the relative position 
the surface of the mercury in the vessel bears to the level of 
the sea, where the mean pressure of the atmosphere will sup- 
port a column of mercury of 30 inches in height. The pressure 
of this column on a base of one square inch, will equal the 



86 PROPERTIES OF STEAM. 

weight of 30 cubic inches of mercury, which weigh just 15 lbs. ; 
which is the pressure of the atmosphere upon a square inch of 
surface. 

15. This fact being established, it remains to show how it is 
to be applied to measuring the elastic force of steam. 

16. A tube is provided, which is bent up like an inverted 
syphon, or in the shape of the letter U, and the bent part filled 
up to a certain level with mercury ; if one end of this be attached 
to the vessel in which the steam is generated, and the other end 
©pen to the atmosphere, when the steam exerts a pressure on 
the surface of the mercury (in the leg of the syphon to which 
it has access) greater than the atmospheric pressure, the sur- 
face in the other leg will rise in proportion, and the difference 
of level between the two will be the measure of the excess of 
steam over the atmospheric pressure. 

17. The following table will show the elastic force of steam 
at various degrees of temperature — the result of minute and 
careful inquiry. The names of the experimentors and the re 
suits obtained being placed in juxta-position, for the purpose of 
comparison. 



PROPERTIES OF STEAM. 



87 



TABLE III. — Comparative of the Results of a series of Ex- 
periments on the Elastic Force of Steam. 





Robison's. 


Dalton's 


Ure's. 


Southern's 


Taylor's. 




Tempe- 












Rule. 


rature. 


Experim't. 


Experim't. 


Experim't. 


Experim't. 


Experim't. 




24° 




# m 


0.170 






0.118 


32 


0.0 


0.2 


0.200 


0.16 








0.172 


36 


- . . 


*0.29 


. 


, . 








0.201 


40 


0.1 


. 


0.250 










0.245 


42 


. 


. 




0.23 








0.266 


43| 


. 


0.297 




i . 








0.281 


50 


0.2 


. . 


0.36 


t . 








0.37 


52 


. 


. 


, . 


0.35 








0.401 


54 i 


. 


0.435 












0.442 


55" 


. 


. , 


0.416 


. 








0.45 


60 


0.35 


. . 


0.516 


. . 








0.55 


62 


. . 


. t 




0.52 








0.587 


64 


. . 


*0.75 


. 










0.633 


65f 


, 


0.63 


. 


, , 








0.675 


70 


0.55 




0.726 










0.78 


72 


. 


. 


. 


0.73 








0.842 


77 


. 


0.91 












1.00 


80 


0.82 


, . 


1.010 


. # 








1.106 


82 


. 


. 




1.02 








1.1S2 


88^ 




1.29 


. 


, g 








1.447 


90 


1.18 


. . 


1.36 


. 








1.53 


92 


. 


. . 




1.42 








1.629 


96 




*1.95 












1.84 


99J 


. 


1.82 




. m 








2.05 


100 


1.6 


. 


1.86 










2.08 


102 


. 


, 




1.96 








2.21 


110 


2.25 


. 


2.456 


m . 








2.79 


nof 


. 


2.54 


u m 


m m 








2.85 


112 




. 


, t 


2.66 








2.95 


120 


3.0 


. 


3.30 


. . 








3.68 


122 


. 


3.5 




3.58 








3.89 


130 


3.95 




4.366 


t , 








4.S1 


132 


. . 


*5.07 


# . 


4.71 








5.07 


133J 


. . 


4.76 


, 


m , 








5.24 


140 


5.15 


. 


5.77 










6.21 


142 


. 


. 


, , 


6.10 








6.55 


144J 




6.45 


# . 










6.95 


150 


6.72 


. 


7.53 










7.94 


152 


. . 






7.90 








833 


155-3 


. . 


8.55 












9.10 


160 


8.65 


. . 


9.60 


. 








10.05 


162 


. . 






10.05 








10.52 


167 




11.25 


• • 


. • 








11.7 



88 



PROPERTIES OF STEAM. 



TABLE TIL— Continued. 





Robison's. 


Dalton's 


Ure's. 


Southern's 


Taylor's. 




Tempe- 












Rule. 


rature. 


Experim't. 


Experim't. 


Experim't. 


Experim' t. 


Experim't. 




170° 


11.05 


, t 


12.05 




. . 


12.6 


172 


. 




. , 


12.72 




, . 


13.17 


173 




*13.'l8 


. . 






. 


13.46 


178J 




14.6 


. 








15.1 


180 


14.05 


. 


15.16 






. 


15.67 


182 








16.01 




. 


16.35 


189J 




18.8 


. , 






. 


19.15 


190 


17.85 


. 


19.0 








19.35 


200 


22.62 


. 


23.60 






. 


23.77 


200f 




24.00 











24.07 


210 


28.68 


. 


28.88 






. 


28.86 


212 




30.00 


30.00 


30.00 


30.00 


30.00 


220 


35.8 


*34.20 


35.54 




34.95 


34.92 


225 


. 




39.11 




. 


38.32 


230 


44.5 




43.10 




41.51 


42.00 


240 


54.9 


. 


51.70 




50.00 


50.24 


250 


66.8 


. 


61.90 




59.12 


59.79 


250.3 


, 


. . 


, # 


60.00 


. 


60.00 


260 


80.3 


. . 


72.30 




70.10 


70.8 


270 


94.1 


. 


86.30 




82.50 


83.45 


272 




*88.9 






. 


86.2 


280 


105.9 


. 


101.90 




97.75 


97.92 


290 




. . 


120.15 




114.50 


114.4 


293.4 




. 


. 


. 


120.00 


. 


120.50 


295 






. . 


129.00 




. 


123.5 


300 






, t 


139.70 




133.75 


133.2 


310 








161.30 




. 


154.5 


312 








/ 167.00 
\ 165.5 






159.0 


340 






*231.0 






236.0 


343.6 




, 




, . 


240.00 




247.80 


320 




. 


. • 


. • 




179.40 


178.5 



19. Thus, having placed before the eye what has been done 
by accurate experiment, we proceed to the rules for calculation 
deduced therefrom. 

20. Rule 1 . To find the force of steam in inches of mercury, 
the temperature being given. 

Add 100 to the temperature, and divide by 177 ; the sixth 
power of the quotient is the force in inches. 

Example. To find the force of steam for the tempera- 
ture of 312. 



PROPERTIES OF STEAM. 89 

312+ 100 4- 177 = 2.3277; 
and 2.3277 3 = 159 inches, the number for the force of 
steam in inches of mercury. 

21. Rule 2. The force of steam being given to determine 
its temperature. 

Multiply the sixth root of the force in inches by 177, and 
subtract 100 from the product, and the remainder will be the 
temperature required. 

Example. Let the force of steam be 8 atmospheres, or 240 
inches of mercury to find its temperature. The sixth root of 
240 may be easily found by a table of squares and cubes, by 
first finding its square root, and then the cube root of the square 
root. 

Thus the square root of 240 is 15.492, and the cube root of 
15.492 is 2.493 ; hence (2.493 X 177— 100 = 341.20. 

22. From the remarks already made in a former part of this 
chapter (art. 6), it will be understood, that when salt water is 
used for the production of steam, the force of the steam will be 
different, as it boils at a different temperature to fresh water. 

23. The rules, therefore, just given will, when applied to salt 
water, require some correction ; that is, the constant number 
which corresponds to a force of 30 inches of mercury, at the 
boiling point, with different degrees of saturation with salt, 
must be supplied, instead of the constant number for common 
water. 

24. The following table gives the various boiling points, and 
constant numbers for different degrees of saturation. 



12 



90 



PROPERTIES OP STEAM. 



TABLE IN .—Of Boiling Point of Salt Water, $c. 



Proportion of 

Salt in 100 parts 

by weight. 


Boiling 
point. 


Constant 
number. 


Constant 
log. 


Saturated i QC f>*y lo 
solution, l&O.&l 33- 


226° 


185.0 


2.267C3 


33.34=1L 


229.9 


184.3 


2.26556 


30.30=^ 


223.7 


183.6 


2.26396 


27.28=A 


222.5 


183.0 


2.26234 


24.25=3 8 3 


221.4 


182.3 


2.26086 


21.22=^ 


220.2 


181.6 


2.25923 


18.18=3 6 3 


219.0 


181.0 


2.25760 


15.15=3 5 3 


217.9 


180.4 


2.25610 


12.12=3 4 3 


216.7 


179.7 


2.25446 


9.09=3^3 


215.5 


179.0 


2.25281 


6.06=3% 


214.4 


178.3 


2.25130 


Water, \ ^•^^ == 33" 


213.2 


177.6 


2.24950 


Common ) f\ 
Water, £ u 


212. 


177.0 


2.24797 



25. According to an analysis made by Dr. John Murray, 
10,000 parts of sea water, of the specific gravity 1.029, con- 
tain 

Muriate of soda, 220.01 = J% 

Sulphate of soda, 33.16 = 3^2 

Muriate of magnesia, ....... 42.08 =2T§ 

Muriate of lime, 7.84 = T ^y6 

303.09 = 3V 

or one part of sea water contains .030309 parts of salts, which 

equals 3V of its weight. 

26. To enable the engineer, or person using the boiler, to 
ascertain with a considerable degree of accuracy the exact pro- 
portion of salt that is held in solution by the water he is then 
using, a little instrument is used, called the salinometer, of 
which the following is a description : — 

A is a small glass tube, having an enlarged part C, to render 
it bouyant, and having a globe or bulb B below that, filled to a 
certain extent with very fine shot or quicksilver, which serves to 
keep it in a vertical position when immersed in water, and also 
causes the instrument to sink to a certain depth. D is an index 



PROPERTIES OF STEAM. 



91 



of paper fixed in the inside of the tube with certain marks and 
figures thereon, which we shall explain in describing its adjust- 
ment. 

Diagram 1. 

27. Many persons are in the habit of adjusting 
their own instruments, to suit either their particular 
systems of calculation or according to their ideas 
of convenience. The process of adjustment is as 
follows : — The top of the tube A is open, and a 
vessel of rain water procured, of sufficient depth, 
to allow the immersion of the tube to extend to 
nearly its whole length. Fine dust shot or quick- 
silver is then poured into the tube, which falls into 
the bulb B, and causes the tube to sink down to 
the required depth ; a mark is then carefully made 
on the tube at the level of the water. The tube 
is then withdrawn; and supposing the vessel to 
contain exactly one gallon of water, having decided 
upon what proportions he will use, the person puts 
in, say 1 oz. of salt, which being entirely dissolved, 
he again inserts the tube, owing to the increased specific 
gravity of the water, the tube does not sink so deep as be- 
fore ; he marks as before the level of water, and repeats the 
operation until he has gone high enough ; he then marks on 
a small slip of paper the different levels he has already noted, 
and opposite to them the number of parts of salt held in solu- 
tion, either calculating by weight or bulk. This paper is 
attached by gum or other means inside the tube, and in the 
proper position ; the end is then hermetically sealed by means 
of the blow-pipe, and the instrument is complete. 

According to the number of quantities of salt admitted and 

their correspondent marks, will be the value of the instrument. 

28. Thus, therefore, with this instrument and the foregoing 

table, any person can tell accurately the amount of temperature 

required to produce a given effect or pressure in the steam ; 




92 PROPERTIES OF STEAM. 

that is, within the bounds of the table, which will rarely be 
exceeded. 

29. We now proceed to consider the motion of steam, and 
the readiest way of investigating the subject will be to ascertain 
the height of a column of the same fluid which shall exert a 
pressure equal to the pressure to which the steam is subjected. 
Then the fluid will rush into a vacuum with the same velocity 
that a ponderous body would acquire in falling through the 
height of the above mentioned column — due reduction being 
made for the contraction of the aperture or passage. 

30. From experiments already made, it appears that an action 
takes place tending to retard the motion of steam in the passage 
of apertures the same as in water. 

TABLE V.— Of Motion of Elastic Fluids. 



The velocity of motion that would result from the 
direct unretarded action of the column of the 
fluid which produces it being unity . . . 

The velocity through an aperture in a thin plate 
by the same pressure, is 

Through a tube from two to three diameters, pro- 
jecting outward 

Through a tube of the same length, projecting in- 
ward 

Through a conical tube or mouth-piece, of the form 
of the contracted vein 



1.000 or 8. 
.625 or 5. 
.813 or 6.5 
.6S1 or 5.45 
.983 or 7.9 



32. As the force of steam is variously expressed by pounds 
on a square inch, by inches of mercury and by atmospheres, we 
subjoin a table of the height of a column of water, which is equal 
to the above measure. 

C 1 lb. per square inch, ... 2. 31 feet. 

Height of a column j 1 lb. per circular inch, . . 2. 94 feet. 

of water at 60° = | 1 inch of mercury, 1 .333 feet. 

[ the atmosphere, 34.00 feet. 

Then, by multiplying any of the terms by the relative bulk and 
pressure, the height of the column of steam will be found. 

33. The rule for finding the volume or space of the steam 



PROPERTIES OF STEAM. 93 

produced from a cubic foot of water at any given force or tem- 
perature, is as follows : — 

Rule. To 459 add the temperature, and multiply the sum 
by 76.5 ; divide the product so obtained by the force of steam 
in inches of mercury, and the result will be the volume or space 
occupied by the steam. 

34. The height of a column of steam being found equivalent 
to the pressure of steam on the boiler, and also the height of 
a column equal to the pressure on the piston, the velocity will 
be equal to 6.5 the square root of the difference between the 
heights of the two columns. This will give the velocity in 
feet per second through a straight pipe ; for other forms or pas- 
sages take the number from table (art. 31). 

35. The rule just stated being for pipes without obstruc- 
tions, and having no data for such pipes as occur in engines, 
allowance must be made for the reduction of speed on the same 
principles which obtain in similar circumstances. Thus -g- of 
the velocity may be deducted for each right-angled bend, -^ 
for an obtuse angle or regular curve ; and if a pipe be ter- 
minated in a valve-box, T 2 o should be allowed for passing the 
valve. 

36. For the purpose, however, of saving time in calculations, 
a table of the properties of steam of various degrees of elastic 
force is subjoined. 



94 



PROPERTIES OF STEAM. 



TABLE VI.— Of the Properties of the Steam of Water of 
different degrees of Elastic Force. 



Total force of Steam. 


tvxcessof force 
above the At- 


gj 

II 

O 


- o 


12 




l»« 


2, S.BC 








mosphere. 


3E 

P 3 

i| 


So 

j= 93 

• O 


asS' 


71 c » 
J2 = p 

« 3 8 

S3 P <J 

? ™ ? 


2, » 


S5 1 


P 
erSS 


p-2J 


•?! 


.0183 


.55 


.21 


-11.33 


-144 


60° 


72190 


6.1 


.0115 


1377 


1008° 


.0333 


1. 


.385 


11.155 


14.2 


77° 


41010 


107 


.0202 


1400 


1025 


.0(567 


2. 


.77 


10.77 


13.7 


98.7 


21400 


20.5 


.0388 


1427 


1047 


.1 


3. 


1.15 


10 39 


13.2 


112.5 


14570 


30 


.0568 


1445 


1061 


.133 


4. 


1.54 


10.0 


12.7 


123.0 


11130 


39.0 


.0744 


1458 


1071 


.25 


7.5 


2.88 


8.66 


10.99 


1476 


6187 


71.0 


.134 


1499 


1096 


.5 


15. 


5.77 


5.77 


7.33 


178.0 


3249 


135.0 


.255 


1526 


1136 


,75 


22.5 


8 65 


—2.89 


—3.66 


197 4 


2232 


196.0 


.371 


1549 


1146 


1.00 


30. 


11.54 


0. * 


0. 


212.0 


1711 


254.7 


.484 


1566 


1160 


*1.17 


35. 


13.46 


*1.92 


*2.44 


220. 


1497 


292. 


.553 


1575 


1168 


1.5 


45. 


17.31 


5.77 


7.33 


233.8 


1178 


363. 


.687 


1591 


1182 


1.75 


52.5 


20.19 


8.65 


10.99 


242 5 


1022 


427. 


.81 


1601 


1191 


2.0 


60. 


23.08 


11.54 


14 65 


250.2 


905 


483 


.915 


1610 


1199 


2.5 


75. 


28 85 


17.31 


21.98 


263.5 


737 


593. 


1.123 


1625 


1212 


3.0 


90. 


34.62 


23.08 


29.3 


274.7 


623 


700. 


1.33 


1638 


1223 


3.5 


105. 


40.39 


,28 85 


36.63 


284.5 


542 


810. 


1.53 


1649 


1233 


4. 


1-4). 


46.16 


34 62 


43.95 


293.1 


479 


910. 


1.728 


1658 


1241 


5. 


150. 


57.7 


46.15 


58.60 


308. 


391 


1110. 


2.12 


1674 


1256 


6. 


180. 


69 24 


57.7 


73 25 


320.6 


331 


1317. 


2.5 


1688 


1269 


7. 


210. 


80.78 


69.24 


87.90 


331.5 


288 


1520. 


2.88 


1700 


1280 


8. 


240. 


92.32 


80.78 


102.55 


341.2 


255 


1660. 


3 25 


1710 


1289 


9. 


270. 


103.86 


92 32 


117.20 


350. 


229 


1910. 


361 


1720 


1298 


10. 


300. 


115.4 


103 86 


131.85 


358. 


20 


2100. 


3.97 


1729 


13U6 


20. 


600. 


230.8 


219.26 


278.35 


414. 


111 


3940. 


7.44 


1786 


1362 


30. 


900. 


346 2 


334.66 


424.85 


450. 


77 


5670. 


1075 


1823 


1398 


40. 


1200. 


461.6 


*450.06 


*571.35 


477. 


60 


7350. 


13 88 


1850 


1425 



* The usual force of low pressure steam. 



37. There is another cause for the reduction of the velocity 
of the steam in its passage to the cylinder, namely, loss of 
elastic force by cooling, which is directly as the surface, and 
inversely as the quantity is exposed. 



CHAPTER II. 

COMBUSTION. 

Production of Steam. — Combination of Combustible Matter.— 
Oxygen. — Means of increasing Combustion. — Blowing 
Cylinders. — Bellows. — Fan. — Table of Dimensions. — Pro- 
perties of Fuel — Comparative Values. — Coals. — Parke's 
Table. — Rules for Calculating Quantities. 

38. Steam being produced by the action of heat upon water 
— and heat being evolved during the process of combus- 
tion — which is effected by the intimate combination of cer- 
tain bodies with a class of substances called supporters of com- 
bustion. In the present case, however, we have to do with 
but one of them ; namely, Oxygen. 

39. Oxygen combines in a greater or, less degree with nearly 
all simple substances ; and the consequence of this combina- 
tion is, the exhibition of a greater or less degree of heat, ac- 
cording to the energy of the action by which the combination 
is effected. 

40. Oxygen forms also one of the principal ingredients of 
which the atmosphere is composed, namely, about one-fifth of 
the whole — and it is from this source that the oxygen is de- 
rived which supports combustion. Therefore, as the oxygen 
during combustion forms a combination with the fuel or com- 
bustible body, it is necessary that its admission be as free as 
possible ; otherwise, if retarded or kept back, combustion de- 
clines or altogether ceases. In many cases, it is absolutely ne- 
cessary that the atmospheric air should be forced into contact 
with the fuel, the supply of air alone not being sufficient to 
produce the required combustion or heat. Here, then, we have 



96 



COMBUSTION. 



recourse to mechanical means, as in the blowing cylinders, for 
the furnaces in which metals are smelted, or in the smaller fur- 
naces called cupolas, used in our foundries for the purpose of 
casting different articles. The commonest and best known ap- 
paratus for assisting combustion is the bellows. 

41. For this purpose, however, the most convenient form is 
that called the fan — more particularly when applied to the fur- 
naces of steam-boat boilers, on account of its facility of opera- 
tion, and the comparatively very small space it occupies. As 
the fan or blower is now getting into very general use, the an- 
nexed diagram, explanatory of its formation and operation, may 
not be misplaced. 

Dug. II. 




42. A, a case or drum of cast iron, having a hole D at either 
end. B, the fan ; C, the spindle, upon one end of which is a 
small pulley, which is connected to a larger one, by means of a 
strap or belt running round the two, and from which it re- 
ceives its motion, varying in velocity according to the force of 
current required ; E, the pipe, or passage for conducting the 
air to the furnace ; F F F, small bolts to retain the sides. 

43. The following table will show the dimensions and ve- 
locities of blowers now in use : 



COMBUSTION. 



97 



TABLE VII. — Showing the dimensions of Blowers now used. 



Diam. 
24 in. 
20 
19 



Depth of Fan. 
6 
4 
4 



Width of Fan. 
12 inches. 
10 
9 



Holes. 
12 in. 
10 
9 



44. In the use of anthracite or stone coal, the blower is of 
very great assistance ; rendering the combustion very complete 
and rapid, and, consequently, raising a greater quantity of 
steam from a given quantity of fuel. Many kinds of blowers 
have been invented and tried, their chief excellence being, appa- 
rently, in their novelty and complication. The conical reacting 
blower attracted much attention at the time of its invention, but 
it has long since ceased to be considered advantageous. 

45. Of the various kinds of fuel in use, the most common in 
this country are four, namely : 

Pine Wood, 

Hard Wood, ' 

Bituminous Coal, 

Anthracite Coal. 
From experiments made on the relative value of the above 
kinds of wood, by Mr. Bull, it would appear that shell-bark 
hickory was the most and white pine the least valuable. We 
subjoin, however, a table of the results, showing the compara- 
tive value of a cord of each kind, together with its weight. 

TABLE VIII. — Comparative value of a Cord of different 
kinds of Wood. 



Kind of Wood. 

Shellbark Hickory . . 
Pignut Hickory . . 
Red-heart Hickory . 
White Oak .... 
Red Oak ... . 
Hard Maple . . . 
Jersey Pine .... 
Pitch Pine .... 
White Pine .... 

13 



Comparative va- 
Weight of Cord. lue of Cord 



4469 lbs. 


100 


4241 « 


95 


3705 " 


81 


3821 " 


81 


3254 " 


69 


2878 « 


60 


2137 « 


54 


1904 <« 


43 


1868 " 


42 



98 



COMBUSTION. 



47. The elative value of the heating powers of bituminous 
and anthracite coal has been variously stated. The following 
table, compiled from the latest experiments, will be found use- 
ful for general purposes : 

TABLE IX. — Comparative value of Coal and Wood. 



P'ts of Litharge lbs. water heated 
reduced. ° by 1 lb. fuel. 



Species of Fuel. 



Oak, seasoned .... 
do. artificially dried . . 

Nut wood 

White Pine 

Yellow Pine .... 
Charcoal ...-». 

Turf 

Charred Turf .... 

Lignite 

Coal, Welsh .... 

" Newcastle . . . 

" Wigan .... 

" Belgium .... 

" Durham .... 
Coke, good 

" inferior .... 

Anthracite, French . . 

" Pennsylvania 



12.5 


4790 


14. 


5350 


13.7 


5240 


13.7 


5240 


14.5 


5550 


25 to 32 




S to 15 




17 to 26 




17 to 27 




31.2 


11840 


30.9 


11S15 


2S.3 


9820 


29. 


11090 


31.6 


12C80 


28.5 


9910 


22.2 


7380 


29. 


11090 


25. 


9560 



49. For the purpose of further facilitating the calculation of 
the cost and consumption of fuel, the following table is added, 
giving the quantity of coal requisite for raising water from 32° 
to 212,° and from 212° for evaporating the same. 

50. The comparative value of bituminous and anthracite 
coal, or bituminous coal and wood, is already given in the 
foregoing tables. This table, therefore, will be sufficient to 
render the calculation of comparative expense or economy a 
matter of very easy access. 

The table was compiled by Mr. J. Parkes, of Warwick, 
England, and published in the second volume of the Trans, of 
Soc. of C. E., London, March 5th, 1838. 



COMBUSTION. 



99 



TABLE X. — Showing the quantities of Coal requisite to 
boil and evaporate. 



Temp, 
of the 
water. 


Coal burnt 

in heating 

to 212 J . 

lbs. 


Coal burnt 

in evapo- 

rat'g from 

212 J . 

lbs. 


Temp. 
wf the 
water. 

94° 


Coal burnt 
in heating 
to 212 J . 

lbs. 


Coal burnt 

in evapo- 

lat'g from 

212 a . 

lbs. 


Temp, 
of the 
water. 


Coal burnt 

in heating 

to 212". 

lbs. 


Coal burnt 

in evapo- 

rat'g from 

212 3 . 

lbs. 


32° 


17.84 


94.16 


12.37 


99.63 


154° 


6.44 


105.56 


34 


17.67 


94.33 


96 


12.18 


09.82 


156 


6.23 


105.77 


36 


17.50 


94.50 


98 


12. 


100. 


158 


.6.02 


105.9S 


38 


17.33 


94.67 


100 


11.81 


100.19 


160 


*5.81 


106.19 


40 


17.16 


94. S4 


102 


11.62 


100.38 


162 


5.6 


106.4 


42 


17. 


95. 


104 


11.43 


100.57 


!64 


5.38 


106,62 


44 


16.83 


95.17 


106 


11.24 


100.76 


166 


5.17 


106.83 


46 


16.65 


95.35 


108 


11.05 


100.95 


168 


4.95 


107.05 


4S 


16.48 


95.52 


110 


10.85 


101.15 


170 


4.74 


107.26 


50 


16.31 


95.69 


112 


10.66 


101.34 


172 


4.52 


107.48 


52 


16.14 


95.86 


114 


10.47 


101.53 


174 


4.30 


107.70 


54 


15.97 


96.03 


116 


10.27 


101.73 


176 


4.08 


107.92 


56 


15.79 


96.21 


118 


10.08 


101.92 


178 


3.86 


108.14 


58 


15 62 


96.38 


120 


9.87 


102.13 


180 


3.64 


108.36 


60 


15.44 


96.56 


122 


9.69 


102.31 


182 


3.42 


108.58 


62 


15.27 


96.73 


124 


9.49 


102.51 


184 


3.20 


108.80 


64 


15.09 


96.91 


126 


9.29 


102.71 


186 


2.98 


109.02 


66 


14.91 


97.09 


128 


9.09 


102.91 


188 


2.75 


109.25 


68 


14.74 


97-26 


130 


8.89 


103.11 


190 


2.53 


109.47 


70 


14.56 


97.44 


132 


8.70 


103.30 


192 


2.30 


109.70 


72 


14.38 


97.62 


134 


8.49 


103.51 


194 


2.08 


109.92 


74 


14.20 


97.80 


136 


8.29 


103.71 


196 


1.85 


110.15 


76 


14.02 


97.98 


138 


8.09 


103.91 


198 


1.62 


110.38 


7S 


13.S4 


98.16 


140 


7.89 


104.11 


200 


1.39 


110.61 


80 


13.66 


98.34 


142 


7.68 


104.32 


202 


1.16 


110.84 


82 


13.48 


98.52 


144 


7.48 


104.52 


204 


0.93 


111.07 


84 


13.29 


98.71 


146 


7.27 


104.73 


206 


0.70 


111.30 


86 


13.11 


98.89 


148 


7.06 


104.94 


208 


0.46 


111.54 


88 


12.93 


99.07 


150 


6.86 


105.14 


210 


0.23 


111.77 


90 


12.74 


99.26 


152 


6.65 


105.35 


212 




112. 


92 


12.56 


99.44 















CHAPTER III. 

BOILERS. 

Neglect of the Subject. — Old Method of Calculation. — Watt's 
Twenty Horse Boiler. — Form and Dimensions. — Capacity. 
— Furnace. — Depth of Water. — Flues and Heating Sur- 
face. — Tubular Boilers. — Form. — Dimensions. — Rule. — 
Action of Fire. — American Boilers. — Improvement. — Loco- 
motive. 

52. Notwithstanding the many and valuable improvements 
which have been added to the machinery and working parts of 
the Steam Engine since the days of the illustrious Watt, it is 
matter of surprise that, until within the last few years, so 
little attention has apparently been paid to the construction and 
use of the boiler. 

53. The extraordinary economy of the steam engine, as 
compared with animal power, is a subject of daily observation ; 
and yet, until lately, no just comparison could be made, as the 
theory and practice of using fuel previously was a subject 
nearly, if not altogether, overlooked. 

54. Form and Dimensions. — In the first place, then, let us 
inquire into the usual form and dimensions of the boiler as used 
by Mr. Watt, and the rules generally employed for calculating 
the size required for an engine of any number of horses' power. 
The system which has hitherto obtained (rule it cannot be cal- 
led) amongst engine and boiler makers, is to endeavour to make 
them larger than necessary ; consequently, a ten horse engine 
will have a twelve or fifteen horse boiler, and a twenty horse 



101 



DlAG. III. 



engine a thirty horse boiler. The usual allowance of water, 
surface and space for each horse power, was about five square 
feet for the former, and twenty-five cubic feet for the latter. — ■ 
The annexed diagram, we will suppose, represents the section 

of a twenty horse 
boiler, 5 feet wide, 
6 feet 8 inches 
deep, and 20 feet 
long ; then, to as- 
certain its contents, 
we must find the 
sectional area, and 
multiply by the 
length. The upper 
part is the half of a 
cylinder 5 feet di- 
ameter and 20 feet 
long; and 5 2 X. 7854 

2 

=196.35 cub. feet. 
The lower part, if 
made with its sides 
and bottom flat, would contain 4.1666X5x20 = 416.66 cubic 
feet ; but the sides are concave, and the bottom also, which re- 
duces the above amount by about one sixth, 41 6.66 =69.44 

b 

cubic feet, and 416.66—69.44=347.22 cubic feet, to which add 
contents of top 196.35=543.57, and 543.57-^-27=20.13 cubic 
yards, which is the capacity of the boiler. One half of this space 
is allowed for water, and the remainder for steam room. But 
some allowance must be made for the stays, which are neces- 
sary on account of the shape ; then about half a cubic yard 
is left for water room, and half a cubic yard for steam room, for 
each horse power. The peculiar form of the sides and bottom is 
to cause the heat, &c. in its passage round the boiler and along 
its bottom, to impinge or press against the sides, instead of 
merely passing by. 




102 BOILERS. 

56. Furnace. — The usual dimensions of the furnace for such 
a boiler are : for the fire bars, five feet long and four feet wide ; 
giving an area of twenty feet, or one square foot per horse 
power. 

57. Depth of Water. — To find the requisite depth of wa- 
ter in the boiler, the following rule is used : Take half the dif- 
ference of capacity between the lower and upper part, and di- 
vide it by the area of water surface, then deduct the quotient 
from the depth of the lower part, and the remainder is the 
depth of water ; measuring from the seating plate of the boiler 
perpendicularly. Thus : 

Capacity of lower part, =347.2-2 
Do upper part, = 196.35 



2)150.87 



Area of water surface = 75.43 

5X20=100 and 
75.43 divided by 100=.7543 quotient ; 
which, subtracted from 4.1666, the depth of lower part, gives 
3.4123 feet, or 40.9476 inches. Hence the requisite depth of 
water was three feet five inches, nearly. 

58. Flues and Heating Surface. — The brick work of the 
side flues is gathered in two or three inches below the water 
level, and consequently the side surface is reduced to about 3.5 
feet, and the total area for both sides is 3.5X2x20=140 
square feet. The area of the ends below the tops of the flues 
is about 28 square feet, minus the surface covered by the brick 
arch over, the furnace door, which about =3 square feet ; and by 
the brick work of the back end which divides the uptake from 
the side flue, which equals about two square feet ; hence these 
numbers subtracted from 28 leave 23, and 23+140 =163 
square feet of surface ; but about one half of this only is 
effective as heating surface, therefore we have only 81.5 square 
feet, or 9.05 square yards. But the whole area of bottom is 



103 



effective ; and, measuring the curved surface, is = about 94 
square feet, or 10.4 square yards ; consequently, the whole 
effective surface = 10.4+9.05 = 19.45, or nearly 20 square 
yards. 

59. From what has been shown of the twenty horse boiler, 
and from experiments made by scientific persons, we find that it 
requires one cubic foot of water to be evaporated per horse 
power per hour ; and one cubic foot of water requires nine 
square feet or one square yard of heating surface, and one square 
foot of fire grate. The ivagon boiler, as this is called, is much 
used in the manufacturing districts of England, and is some- 
times made of enormous size. It answers only for low pres- 
sure steam. 

60. Tubular Boilers. — Where high pressure steam is re- 
quired, tubular boilers (so called) are generally made use of, 
chiefly on account of the shape ; the cylindrical being a much 
stronger form for resisting pressure, either externally or inter- 
nally, than the wagon shape. The diagram below shows a 
section of one with an internal flue and split draught ; that is, 
the smoke passes under the boiler, and through the tube, and 
then divides and returns on each side to the chimney or stack. 

61. The di- 
mensions are 
— in diame- 
ter, six feet; 
length, nine 
and a flue of 
18 inches di- 
ameter, run- 
ning from end 
to end ; and 
the fire grate 
or furnace is 

three feet six inches square, or twelve and a quarter square 
feet area. This boiler, then, according to the rule above stated, 




104 BOILERS. 

would be a nine horse power boiler ; but many who are in the 
habit of making flued boilers, or, as they are commonly (though 
erroneously) called, tubular boilers, usually consider in their 
calculations that the diameter of the inside flue or tube is 
equivalent to so much added to the width of the boiler, the re- 
sult of which is nearly correct, at least in cases where the 
boiler is not very long in proportion. 

According, therefore, to this rule, the power of the boiler is 
found as follows : 

Diameter of boiler =5 feet. 
.Do. of inside flue = 1.5 

6.5 ; 

Multiply by length, 9 

Divide by 5)58.5 

Horses' power, 11.7, or 11 1 nearly. 
By observation, the evaporation of this boiler only varied 
from ten to eleven cubic feet of water per hour. 

62. The next class of boilers are those used for locomotive 
engines, of the peculiar construction of which, more will be 
said under the head of Locomotion. These boilers, or rather 
boilers constructed on the same principles, are now used with 
great success on board many of the steam boats : their ex- 
traordinary power of generating steam being so peculiarly 
adapted to the present system of using the steam engine (viz : 
using high pressure steam expansively) ; as they not only take 
up such little room, but admit of working up to a considerable 
pressure, when necessity may require, in so short a time. 

63. These boilers were first applied by Mr. R. L. Stevens, 
in 1837, who has since made several different constructions, 
all of which answer remarkably well. The plans of several 
of these are shown in the volume of plates. 

64. It would seem, however, that perfection is far from be- 
ing attained in the art of constructing boilers ; for nearly every 



BOILERS. 105 

new boiler has some supposed improvement over the last, at 
least those made by the more intelligent engineers. Some 
manufacturers still use flues, varying in diameter from 8 to 18 
inches, of which they have eight, ten, or more in each boiler. 
Of such construction are the boilers of the steamboat ' North 
America ;' and, from the quantity of steam supplied compared 
with the small quantity of coal consumed, we should pronounce 
these amongst the best now in use — 28.28 cubic feet of steam, 
of the pressure of fifty pounds per square inch being generated 
by the combustion of one pound of coal per minute. 

65. There is yet another modification of boiler, the credit of 
which combination is the property of Mr. R. Schuyler. In this 
boiler (see plate 35), the heat passes off right and left through 
small tubes ; it then enters a long flue, through the top of 
which it passes into other horizontal flues, whence it makes its 
escape to the funnel. This boiler produces 888.864 cubic feet 
of steam, at a pressure of twelve pounds per square inch, with 
the combustion of 7.879 lbs. of coal, per minute, or 112.8 
cubic feet of steam from 1 lb. of coal at the same pressure. 

66. The same enterprising gentleman has constructed seve- 
ral boilers since the above was first put in operation, all of 
which have fully answered his expectations. 

67. Although, in the case of the ' Essex,' he had a very con- 
fined room for his operations — that is to say, the height from 
floor to deck being so limited, as it must necessarily be in boats of 
such small dimensions as ferry boats usually are — nevertheless, 
this boiler may with safety be declared to possess the greatest 
known generative power of any or all the marine boilers that 
have ever been constructed in this country. 

68. Of the boilers used on the Western waters, little can 
be said, as they are merely cylindrical, and similar to that al- 
ready described. 

69. It is well known, though notice of the fact should not be 
omitted, that the surface in actual contact, and in close prox- 
imity to the fire, is many times more valuable than the surface 
which is further off ; hence, in calculating the generating sur- 

14 



106 BOILERS. 

face, care must be taken to make proper allowance for the 
same. Some authors and practical men have denned this pro- 
portion at the rate of 3 to 1, 2 to 1, and 5 to 1; the latter pro- 
bably being nearest to the fact. 



PART III. 



STEAM NAVIGATION. 



CHAPTER^. 

STEAMBOATS, &c. &c. 

70. In the former part of this work we have considered the 
steam engine as made and applied, or ready to be applied to 
the purposes of pumping or raising water, or as the moving 
power for working mills or manufactories. We now, however, 
from its very great importance, turn to the application of this 
mighty power for the purposes of impelling or driving vessels 
either for ocean or inland navigation. 

71. We have already seen to what state of perfection the 
steam engine had been brought in Europe up to the year 1801. 
(See plate I.) It was a double acting engine, capable of pro- 
ducing a continuous rotatory motion, by means of the crank and 
fly-wheel. In the year 1807, Fulton's first steamboat was in 
actual operation on the Hudson — preceding the Stevens' boat 
by a few days, and thus securing to himself the grant of the 
exclusive privilege of the State of New-York. The Stevens', 
however, although deprived of the waters of New- York, sent 
their vessel round by sea to the Delaware, where they imme- 
diately set it in operation. 

72. Fulton, it appears, considered that the wave formed by 
the passage of the boat through the water presented an insur- 
mountable obstacle to the production of any greater speed than 
eight or nine miles per hour ; and this appears to be the speed 
that Fulton assigned for nearly all his boats. 

73. During this period, R. L. Stevens was carefully examin- 
ing into the form and arrangement of vessels best adapted for 
navigation at a greater velocity ; and when the monopoly en- 
joyed by Fulton expired, he had a vessel ready which perform- 
ed the voyage from New-York to Albany at the rate of 13£ miles 
per hour. 



110 STEAM NAVIGATION. 

74. Stevens considered the slow speed of Fulton's earlier 
boats as chiefly attributable to the full bows or bluff entrance 
of the vessel ; and was thus induced to bestow so much more 
attention on the architecture of these boats than he otherwise 
might have done. It is, therefore, most decidedly, to R. L. 
Stevens that we owe the present beautiful models of our North 
River boats, which for elegance and speed are justly considered 
the finest in the world. 

75. The engine which Fulton first obtained from the estab- 
lishment of Bolton and Watt, of Soho, was so made as to allow 
the crank shaft to be raised or lowered, for the purpose of apply- 
ing greater or smaller paddle wheels — the exact dimensions of 
which could only be decided upon by practice. He subsequently 
altered the arrangement of the engine, and made it work like the 
engines of the * Neptune' or ' Daniel Webster,' and it received 
the name of the cross-head engine. The cross-head works in 
guides on each side ; therefore the motion of the piston-rod is 
kept perfectly vertical. The present form, however, of the 
cross-head engine with its many improvements, is unquestion- 
ably the production of Dr. Hart, many years foreman to Mr. 
James P. Allaire, of New-York. 

76. Stevens used the Bolton and Watt engine with some 
alterations. Thus, he took away the parallel motion and substi- 
tuted the guide-rods, as well as most materially improved the 
power of the boiler. 

77. It was not until the year 1812 that steamboats were 
introduced into general use in Great Britain — five years after 
Fulton's successful voyage on the Hudson. 

78. In 1815, Fulton commenced running steamboats from 
New- York to Providence, Rhode-Island, part of which passage 
is performed on the open sea. 

79. In 1817, the steam vessel * Savannah' made a voyage 
from New- York to Russia ; and, 

80. In 1818, a steam ship plied as a regular packet from 
New-Orleans to New-York, touching at Havana and Charleston. 



STEAM NAVIGATION. Ill 

81. In the year 1815, the first passage was made from Glas- 
gow to London, in a steamboat, under the direction of Mr. 
George Dodd. 

82. In 1820, the mail packets were established by the British 
Government to run from Holyhead to Dublin. 

83. In 1825, a passage was made from London to Calcutta 
by the steam ship ' Enterprise.' 

84. From the last date up to the present time, we have 
noticed a gradual improvement, as well in the machine itself 
as in the boilers and shape of the vessels. 

85. In France, the progress of the steam engine, whether 
applied to manufacturing purposes or otherwise used, did not 
arrive at any degree of perfection until long after its successful 
use both here and in England ; a circumstance which is attri- 
butable to the agricultural pursuit of its inhabitants, more than 
to any want of energy amongst the learned philosophers of that 
country. 

86. We now come to an entirely new era in steam naviga. 
tion, namely, the introduction of the system of using steam 
eocpansively ; a system which we have already shown, was 
patented by Watt in 1778, and subsequently used with the 
most beneficial effects in connection with high pressure steam, 
by the engineers of Cornwall, who have fully tried and tested the 
merits of the system for many years, especially as to its eco- 
nomical qualities ; the result is, that nearly every engine in use 
at the various mines in that country (and there are some hun- 
dreds of engines employed), are condensing engines, working 
with high steam, and using it expansively. The actual amount 
of saving has been variously estimated at from 75 to 50 per 
per cent. 

87. Taking advantage of the above mentioned facts, Mr. 
Adam Hall (long the foreman at the West Point foundry), 
conceived the idea of using high steam, and cutting off the sup- 
ply at |, I, or even \ of the stroke ; thereby anticipating a 
saving, not only in the actual consumption of fuel, but also in 
time, by obtaining a greater velocity. 



112 STEAM NAVIGATION. 

88. The first impulse being given, or rather the attention of 
the wealthy speculators in steam navigation being called to this 
circumstance, trials were immediately made, and their results 
proving every way satisfactory, the system at once obtained, 
and now it is the common practice of our engines to adopt the 
cut-off valve to all kinds of engines. 

89. The many beneficial results springing from this cause 
induced others to enter upon the examination of the subject ; 
and it was found by experiment and established by practice, 
thatmore work was done at a less expense by cutting off at ^th, 
than by cutting off at I the stroke ; the pressure of the steam 
in the boiler being of- course increased in proportion. Thus, 
the steamboats lately constructed, cut off at k, }, and some even 
at -i.-th of the stroke, and the results are highly satisfactory. In 
another point of view, this has great advantages over the method 
of using dense steam (i. e. of allowing the cylinder to be filled at 
each stroke), in the fact of its only requiring I, ~, or y^th part 
the quantity of steam, thus requiring less boiler room and fuel — 
no inconsiderable desideratum in a steamboat. Many persons 
there are, however, who still persist in arguing (in the face of 
facts), that it is no more economical to use high than low pres- 
sure steam with the cut-off. We would advise those persons 
to ascertain how many pounds of coal are consumed per horse 
power per hour on board the new ' North America,' and compare 
that amount with the quantity used in the boats of an earlier 
date, and we are much mistaken if they will not find a saving 
of at least 50 per cent, in fuel, to say nothing of the speed, which 
has been just doubled. 

90. The theory of high pressure expansive steam, we may 
safely venture to say, is not yet understood ; and many persons 
who have attempted to analyze its operation and action, have 
most signally failed, either from the want of sufficient data, or 
from some misconception of its nature. So little, indeed, is the 
principle understood in England generally, even at the present 
day, that the work performed by the Cornish engines, for the 
fuel consumed, is hardly credited, nay, has been flatly denied 



STEAM NAVIGATION. 113 

by some of the London engineers ; the amount of work done 
so far exceeding what is usual for the best engines working 
with low pressure steam, although using it expansively ; which 
plan, however, is infinitely more economical than not cutting 
off at all. 

91. By means of the * Indicator, or Dynamometer, we can 
ascertain with considerable exactness what the engine is doing ; 
and then, by knowing the quantity of coals consumed, we can 
arrive at the actual expense of the work done. It is by these 
means that the Cornish pumping engines are tested ; and as the 
instrument is perfectly accurate in its results, there can be no 
doubt that the data of the calculations are correct. 

92. To enable the reader to see clearly, for himself, the effect 
of the cut-off with high steam, we give the following well at- 
tested experiment on a celebrated Cornish engine, taken from 
a paper by Mr. Wicksteed, and read before the Society of Civil 
Engineers, of London, in the year 1837. 

"I am induced to address you again (see vol. i. of Trans, of 
S. C. E.), on the subject of the engines used in the mines in 
Cornwall, from the very kind manner in which you received 
my last paper. 

" I have been lately into Cornwall, having been instructed by 
the Directors of the East London Water Works Company to 
proceed there, for the purpose of examining an engine that was 
to be disposed of by the East Cornwall Silver Mining Com- 
pany, with a view of purchasing it for the Company's works, 
at Old Ford. The result was, that the engine, the cylinder of 
which was 80 inches in diameter, was purchased, and is now 
being removed to London, and I expect by this time next year, 
will be at work here. 

" While in Cornwall, I was very desirous of making such a 
trial of one of the engines, as might be satisfactory to the 
London Engineers, and trust that I have succeeded in my 
object. 

* For description, see Part V. 
15 



114 STEAM NAVIGATION. 

" I received permission to make a trial of the engine upon 
the Holmbush mines, near Callington, and beg to give you the 
following detailed account thereof : 

The diameter of the cylinder was fifty inches ; the size of 
the pumps, or ' boxes,' as they are termed in Cornwall, and the 
height of the lifts are as follows, viz : 

Tye lift, 42 fath. 2 ft. 6 in. | Diam of pump, 11 in. 
Rose lift, 37 " 5 " 6 do 11 " 

Bottom lift, 8 " 5 " 6 do 10 " 

" The chief points to which my attention was directed, were 
the quantity of coal consumed, and the actual quantity of wa- 
ter lifted. 

.."I saw 94 lbs. (a Cornish bushel) of coals weighed, and 
had the stoke-hole cleared, and the coal-bins and stoke-hole 
doors sealed ; and in addition to these precautions, besides my 
own observation, I had one of my young men stationed in the 
boiler house during the time of trial, so that I am quite satis- 
fied that no more than 94 lbs. of coals were used. 

" Before the trial, I ascertained exactly the length of the 
pump stroke, which was eight feet one inch, and caused the 
engine to work slowly, that I might have sufficient time to 
measure the quantity of water delivered per stroke. The wa- 
ter was delivered in a wooden cistern, with a valve to let the 
water out, when I had measured it. Finding that six separate 
measurements produced as nearly as possible the same result, 
the greatest variation being two per cent., I weighed the 
quantity of water delivered by each stroke, and found it to be 
equal to 285^ lbs. I had a rod made the exact length of 
the stroke, namely, eight feet one inch, and during the trial 
measured the stroke frequently ; it varied from eight feet one 
inch, to eight feet two inches. I have in my calculation taken 
the shortest length. The diameters of the pumps and exact 
height of the lifts were taken very carefully. 

Trial. — The fire under the boiler was worked down as low 
as could be, without stopping the engine. The pressure of the 
steam was forty pounds to the square inch in the boiler. I 



STEAM NAVIGATION. 115 

took the counter and the time, and then started the engine. 
At the end of two and a half hours the fire was lowering, and 
the speed of the engine reducing, and it was necessary to have 
more fuel. The 94 lbs. having been consumed, the engine 
was then stopped, and the counter again taken. It had made 
672 strokes, or very nearly five strokes per minute. The 
weight of water raised was (285.6x672 strokes)=191,823.2 
lbs. ; the height to which it was raised was (42 fath. 2 ft. 
6 in.+37 fath. 5 ft. 6 in. + 8 fath. 5 ft. 6 in.)=535 ft. 6 in. ; the 
weight multiplied by the height in feet, is equal to 102,721,- 
323 lbs. of water lifted one foot high with 94 lbs. of coal. 

This result, however, although it shows how much water 
was actually raised to the surface, does not show the duty of 
the engine ; for although, in consequence of leaks and defective 
valves, the quantity raised is not so great as it would be were 
it possible to have every part perfect, nevertheless, the engine 
has to raise the quantity due to the areas of the pumps, multi- 
plied by the length of the stroke, under the pressures due to the 
columns of water equal in height to the lifts, notwithstanding 
that, in consequence of the defects mentioned, the whole quan- 
tity may not reach the surface ; the fair mode, therefore, of 
calculating the duty of the engine, during the trial, would be as 
follows : 
Weight of column of water, 11 inches diam., and 

42 fath. 2 ft. 6 in., or 254.5 feet high, 10,498 lbs. 

Do do 11 inches diam., and 

37 fath. 5 ft. 6 in., or 227.5 feet high, 9,384 lbs. 

Do do 10 inches diam., 8 

fath. 5 ft. 6 in., or 52.5 feet high, 1,824 lbs. 



Load upon engine, 21,706 lbs. 
21,706 X 672 strokes X stroke 8-^ feet, =117,906,992 lbs. 
weight, lifted one foot high with 94 lbs. of coal. 

"From the foregoing, it will be seen that 191,823 lbs. of 
water were raised 535 feet 6 inches high, with the expenditure 
of 94 lbs. of coals ; and that the duty of the engine was 



116 STEAM NAVIGATION. 

equal to nearly one hundred and eighteen millions of pounds 
raised one foot high. I should observe that the engine had not 
been overhauled, or any thing done to it to prepare for the trial, 
which was not determined upon (as regarded the engine upon 
which the trial was to be made) until the previous day. The 
boiler and flues had not been cleaned for eleven months. My 
object was to prove what could be done by an engine worked 
upon the expansive principle, and I therefore considered that a 
trial for two hours would prove the capability of the engine, 
although, most probably, the average duty of the engine for 
twelve months, would not be so great as it was for the short 
time that it was under trial. I am perfectly satisfied the trial 
was a fair one. 

" I was not able to ascertain what the pressure of steam was 
when it first entered the cylinder, having no indicator with me ; 
but the engineer, Mr. West, stated that the steam was wire- 
drawn, and reduced from 40 lbs. above the atmosphere, 
(which was the pressure in the boiler) to 30 lbs. above the 
atmosphere, upon entering the cylinder. 

" The steam was cut off at one-sixth the stroke. The steam 
in the jacket round the cylinder communicates directly with the 
boiler, and radiation is completely prevented by the casing 
round the jacket ; consequently, a high temperature is pre- 
served, which is absolutely necessary to obtain the full effect 
from the expansive force of the steam. 

" The following will show what effect could have been pro- 
duced by the steam power, provided the engine and pump gear 
had worked ivithout friction : 

Pressure of steam when first admitted into the cylinder, (30 
lbs. -f- 14.75 lbs. — 1.5 for imperfect vacuum)=43. 25 pounds. 



STEAM NAVIGATION. 1 1 

For J of the stroke, the pressure was per sqr. inch, 43.250 lbs. 
When the piston had made § of its 

stroke, the pressure was reduced to 21.625 " 

Do f 14.416 " 

Do f 10.812 " 

Do | 8.650 " 

Do | 7.208 " 



6)105.961 " 



Mean pressure of steam, 17.66 lbs. 



The area of cylinder was 1963.5 square inches. 

Mean pressure of steam per sqr. inch, 17.66 lbs. 
Number of strokes, 672 

Length of stroke in cylinder, 9 ft. 1 inch, 

(being one foot longer than in shaft.) 

Power of steam, 1963.5 square inches X 17.66 lbs. per 
square inch, X 672 strokes X 9 T 1 2, length of stroke, =21 1,658,- 
702 lbs. raised one foot high with 94 lbs. of coals ; and 
now, as the effect produced was 117,906,992, the friction of 
the machinery was equal to 93,751,710 lbs. raised one foot 
high, or about 7} lbs. pressure per square inch. As the 
friction of a water works pumping engine is about 5| lbs. 
per square inch, it may be safely inferred that an engine, when 
working on the expansive principle, at a water works, will do 
more work than it does in the mines. To those who have seen 
the heavy pump-rods, balance-bobs, &c, attached to a mining 
engine, it will appear very evident. 

In the observations I have had opportunities of making, I am 
very well satisfied that the engine I am about to erect at the 
East London Water Works, will do a duty equal to at least one 
hundred and twenty millions lbs." 

From the foregoing we plainly see the economy — or rather 
trifling cost of work done — as far as the mere fact of raising wa- 
ter is concerned. We will now continue with Mr. Wicksteed's 



118 STEAM NAVIGATION. 

paper, and see if any beneficial effects are apparent when using 
high expansive steam in a double acting rotative engine : 

"As it had been observed that the expansive principle would 
not answer for rotary or double engines, I was induced to make 
some observations on a double engine, working the stamps for 
breaking the copper ores, at the Tincroft mines, and I beg 
leave to give you the details : 

The diameter of cylinder, 36 inches. 

Length of stroke, 9 feet. 

Length of crank, 3 " 6 " 

Steam was cut off in down stroke, at ± 

Do up stroke, at | 

Number of strokes per minute, 10 

" The engine worked with a very equal velocity ; in fact, 
there appeared no irregularity whatever in the motion. Capt. 
Paul, the agent of the mine, allowed me to examine the 
coal accounts, from which it appeared that the average con- 
sumption of coals for the engine was 30 bushels for 24 hours. 

The engine was working — 1st, a set of stamps; 2d, a 
pump ; 3d, a crushing machine ; and 4th, a trunking machine. 
The last two pieces of machinery had lately been added ; and 
previous to this increase of machinery, it appeared from the 
books, that the consumption of coals was equal to 27 bushels, 
of 93 lbs. each, in 24 hours. 

" The stamping machinery worked 48 lifters ; to ascertain the 
weight of them, I examined an account showing the weight of 
26 of the cast iron heads, when new, and found the average 
weight to be 3 -cwt. 12 lbs. each; these are used until the 
weight by wear is reduced to 1 cwt. 2 qrs.; the average weight 
will therefore be (3 cwt. 12 Ibs.+ l cwt. 2 qrs.-^2)=2 cwt. 
1 qr. 6 lbs. The weight of the wood-work of the lifter, the 
iron straps, washers, &c, I found by trial to be 1 cwt. 3 qrs. 
24 lbs., making the total average weight of the lifter and head 
(2 cwt. 1 qr. 6 lbs.-fl cwt. 3 qrs. 24lbs.)=4 cwt. 1 qr. 2 lbs., 
or 478 lbs. The average height the stamps were lifted was 10 
inches, and the 48 stamps were lifted five times per stroke. 



STEAM NAVIGATION. 119 

" The following calculations will show the duty performed 
by 'he stamping engine : 

Forty-eight lifters x478 lbs.xO.S33 feet, height lifted, X 5 times 
per strokeXlO strokes per minuteX60 minutes per hour X 24 
hours per diem= 1,376,089,344 lbs., lifted one foot high in 24 
hours. 

The diameter of the pump was 14 in., or 1.069 sqr. ft. area. 
Length of stroke, 6 feet. 

Strokes per minute, 10 

Lift, 26 feet. 

Duty Performed— 1.069 sqr. ft.X6 ft.x62jxlbs per cubic 
footx26 feet liftxlO strokes per minutex60 minutesx24 
hours = 150,087,600 lbs., raised 1 foot high in 24 hours. 

Duty of Engine— 1,376,089,344+150,087,600-4-27 bush- 
els = 56,525,072 lbs. lifted one foot high with a bushel, or 93 
lbs. of coals. 

" The single engine at the Holmbush Mine was, during the 
time of my experiment, doing the work of 26.48 horses. Thus, 
the experiment lasted 2\ hours, or 135 minutes, x 33, 000 lbs. 
lifted 1 foot = 4,455,000 lbs., which would be lifted 1 foot high 
by the exertion of one horse's power in 2\ hours; 117,906,- 
992 lbs.4-4,455,000 = 26.4S horses' power. The coals con- 
sumed were equal to 94 lbs., or (94-4-26.48-4-2.25 hours) = 
1.57 lbs. of coals per horse power per hour. The coals used by 
one of the pumping engines at Old Ford, in an experiment 
lasting one hour, tried upon the 18th February, 1835, were 
equal to 4.82 lbs. per hour per horse power, or three times the 
consumption of the Cornish engine, notwithstanding the extra 
friction in a pumping engine. 

" The double engine at the Tincroft Mines was doing the 
work of 32.11 horses. Thus, 33,000X60 minutes X 24 hours == 
47,520,000 lbs., lifted 1 foot high by the exertion of one horse 
power during the 24 hours. The engine lifted 1,526,176,944 
lbs. 1 foot high in the 24 hours ; 1, 526, 176,944-r 47,520,000 = 



120 



STEAM NAVIGATION. 



32.11 horses' power. The coals consumed were 27 bushels, 
of 93 lbs. each, or 2511 lbs. -r- 24 = 104.62 lbs. per hour 4-32.11 
horses' power= 3.25 lbs. of coals per hour per horse's power. 
" Mr. Farey, in his valuable treatise on the Steam Engine, 
states that a rotary or double engine of Bolton and Watt's con- 
struction, will require 10J lbs. of coals per hour per horse's 
power, or three times the consumption of the Tincroft double 
engine." 



93. The following tables may prove interesting. The first is 
a chronological table, exhibiting the gradual improvement of 
the steam engine (as applied to working mines) in the course 
of sixty-six years. The second table exhibits the average duty 
performed by the engines in Cornwall, in 1835 and 1836, in- 
cluding old and new engines, and all sizes. 
TABLE XL 





bs. raised 1 foot high, with 


lbs. of coal per 


Date. 


he consumption of 1 bushel 


hour, per horse 




:>r 94 lbs. of coal. 


power. 


1769 


5,590,000 


33.33 


1772 


9,450,000 


19.70 


1786 i 






to V 


20,000,000 


9.30 


1800) 






1813 


28,000,000 


6.64 


1814 


34,000,000 


5.47 


1815 


50,000,000 


3.72 


1825 


54,000,000 


3.44 


1827 


62,000,000 


3. 


1828 


80,000,000 


2.32 


1834 


90,000,000 


2.06 


1836 


97,000,000 


1.91 


Trial of Fowey ) 
Consol's En- S-l 835 
g ne in ) 






125,000,000 


1.48 



The above table was compiled by Mr. John Taylor, an au- 
thority that cannot be disputed, from authentic accounts pro- 
cured by himself in Cornwall. 



STEAM NAVIGATION. 



121 



TABLE XII. 







Average lbs. 


Av. load 


Average 


Highest duty 


Lowest duty 


o &£ 


No. ol 


Diam. 


raised 1 foot 


on piston, 


number ol" 


in lbs., raised 


in lbs., raised 


a- 5 § 


Erie's. 


of cyl- 


with 941bs. of 


p. square 


strokes p. 


I foot with 94 


1 foot with 94 


J"! 6 




inder. 


coal. 


inch. 


minute. 


lbs. coal. 


lbs. coal. 


H £ ,S 


4 


90 


47,S29,S30 


8.971 


6 707 


61,884,427 


35,775,624 


22 


3 


85 


71,146,686 


11.643 


5.761 


77,311,413 


63,172,606 


17 


7 


SO 


66,^44,570 


10.989 


5.351 


97.595,571 


37,059,128 


18 


2 


76 


47,6S5,167 


12594 


5.071 


65,345,4 7 


40,457,463 


22 


5 


70 


52,009,587 


9.672 


5416 


SI, 026,642 


22,313,025 


20 


3 


66 


49,734,514 


7.965 


5.379 


77,446,214 


24,277,768 


20 


2 


65 


54,921,572 


14.57 


3.098 


63,411,061 


43,126,101 


22 


1 


64 


50,107,225 


10.74 


5.83 


39,625,677 


19,344,343 


17 


6 


60 


48,656,046 


10.819 


5.73 


76,673,995 


29,233,376 


18 


1 


58 


61,317,268 


1229 


.945 


67,115,413 


55,366,495 


12 


1 


56 


38,059,440 


12.826 


3.452 


46,509,910 


30,656,541 


8 


1 


53 


44,46S,465 


16. 


2.S95 


58,624,253 


40,294,578 


6 


6 


50 


43,645,480 


9.89S 


5.075 


60,723,738 


31,587,345 


18 


1 


45 


4S,137,083 


18.35 


6.137 


55,564,549 


41,268,911 


8 


1 


42 


40,712,991 


16.199 


8.667 


46,132,677 


36,499,814 


23 


1 


41 


49,052,474 


16.228 


5.SS4 


57,288,816 


42,081,037 


22 


6 


40 


45,591,848 


11.196 


5.356 


64,400,208 


24,962,485 


12 


1 


39 


31,286,192 


11.451 


3.13 


39,427,731 


25,395,105 


23 


9 


36 


33.277,832 


12.781 


6.357 


47,884,690 


17,619,529 


13 


1 


33 


30,245,394 


15.927 


6.4 


36,265,146 


22,938,142 


23 


4 


30 


38,828,948 


13.838 


7.039 


74,897,208 


19,344,343 


17 


1 


26 


31,529,39617.56 


8.26 


34,943,591 


27,697,031 


14 


1 


25J 


28,248,292117.6 


11.555 


32,431,160 


20,773,914 


23 


3 


24 


35,377,38713.682 




47,101,689 


20,562,859 


21 



" I cannot conclude this paper without acknowledging the 
great attention I received from the intelligent engineers and cap- 
tains of the mines in Cornwall, whom I found, as in my former 
visit, most anxious to give every facility to those parties who visit 
the county for the purpose of obtaining information ; and notwith- 
standing their own thorough conviction of the advantages of 
the system they adopt, and of the truth of the statements 
made in the monthly reports, they were in every instance most 
desirous of removing the doubts that others might have, by 
permitting any trials to be made, and by most readily and openly 
giving any information that might be required. 

"THOMAS WICKSTEED. 

"Old Ford, Aug. 7, 1837." 
16 



122 ■ ( STEAM NAVIGATION. 

94. As to the actual economy, we would merely call atten- 
tion to the following statement of the gross quantity of water 
raised by three different Cornish engines, one foot high, for 
the expense of one farthing sterling, viz : 

Huel Towan — Wilson's engine, 1,085 tons ; 
Binner Downs — Swan's engine, 1,006 " 
East Crinnis — Hudson's engine, 870 " 
The above, and similar statements, caused the unbelief of 
the London engineers ; and, at first sight, it does certainly ap- 
pear an almost incredible amount of work ; but a careful peru- 
sal of Mr. Wicksteed's paper will surely satisfy any person 
who will take the pains to examine the merits of the case. 

95. For fear, however, that there may be some who still 
hesitate, we will insert a short account of an experiment made 
on low pressure steam, by the above named gentleman : 

" On the 18th of February last (1835), I tried the power of 
an engine on this construction (similar to the engine, plate 
5). The experiment lasted one hour, and 469 lbs. of good 
Holywell Main large coals were used. The diameter of cyl- 
inder was 60 inches ; length of stroke, 7 feet 9 inches ; the 
engine made 869 strokes in the hour, or 14.48 per minute ; the 
pressure of steam was 2 J lbs. per square inch above the pres- 
sure of the atmosphere, which was 14| lbs.; the vacuum in 
the condenser, 13j lbs. ; the diameter of the pump was 27 
inches ; the length of the stroke, 7 feet 9 inches ; the pressure 
upon the pump piston was equal to a column of water 115 feet 
in height; load upon pump piston, 28,577 lbs., equal to 10.1 lbs. 
pressure per square inch of the steam piston ; as the pressure 
of the steam, minus 1-J lbs. for imperfect vacuum in the con- 
denser, was 15| lbs., the friction of the engine must have 
amounted to 5.65 lbs. per square inch. 

" The steam used in the hour may be found thus : — the area 
of cylinder was 19.63 square feet, and the steam was cut off 
at 1 foot 3 inches from the end of stroke, making the length of 
stroke for the dense steam 6 feet 6 inches, which multiplied by 
the area, gives 127.6 cubic feet per stroke ; add T V for loss of 



STEAM NAVIGATION. 123 

steam per stroke in the vacancies of the cylinder, making a total 
of about 140 cubic feet of steam per stroke ; which, multiplied 
by the number of strokes per hour (869 X 140), is equal to 
121,640 cubic feet of steam, generated under a pressure of 35.2 
inches of mercury, at a temperature of about 222° Fahrenheit. 

" The " duty" performed was 34,467,052 lbs. raised one foot 
high, with a bushel or 84 lbs. of coals. 

" The power of the engine during the time of trial was 
(28,577 lbs. load X7.75 stroke X 14.48 strokes per minute — 
33,000) equal to 97.2 horses' power. 

" The steam used was 125.1 cubic feet per horse power, to 
produce which, at a temperature of 222° Fahrenheit, would 
require about 0.856 cubic feet of water ; and to convert this 
quantity of water into steam at 222°, it required 4.82 lbs. of 
coals." 

96. Having thus seen the utility of this system, as practised 
in Cornwall, it will be desirable to exhibit its beneficial effects 
here also, as it is used in the steamboats on the North River. 
To enable the reader, therefore, to make comparisons himself, 
the following table has been carefully compiled ; giving, 1st, the 
requisite dimensions ; 2d, the cut-off'; 3d, the pressure of the 
steam ; 4th, the quantity of fuel consumed ; 5th, the amount of 
work done ; 6th, the time of doing the work of several of the 
most celebrated boats on the river. For particular descriptions 
of engines, with their working parts, the reader is referred to 
the tabular statement and explanation of the plates at the end 
of the volume. 

97. Steamboats of the West. — Having thus considered the 
steam engine as used on the Eastern Rivers of the Union, we 
will proceed to notice the peculiar construction and principle of 
those used on the Western waters ; and for the purpose of bet- 
ter enabling the reader to understand the beauty of the arrange- 
ment of these machines, it will be well briefly to point out the 
difficulties to be overcome in the navigation of the mighty rivers 
of that vast country. 

98. From the size and rapidity of these waters, the ordinary 



124 STEAM NAVIGATION. 

method of sails, or oars, is utterly inadequate to produce any 
useful effect in stemming the current. 

99. The produce and manufactures of the upper states, are, 
however, readily conveyed down to New-Orleans, by means of 
enormous flat-bottomed boats, formed by combining large tim- 
bers together, and thus making a superior kind of raft, which, 
when unloaded at New-Orleans, are broken up and sold ; the 
timber of which they were formed having suffered but very 
little damage from its voyage down the river. These flats are 
continually coming down the river ; the persons who navigate 
them have to return, nevertheless, which they would find a very 
fatiguing voyage indeed, if they had no steamboats ; adding to 
this, the enormous traffic required to supply the upper states, 
nearly all of which passes through New-Orleans, the reader 
will readily imagine the importance of having an upward as 
well as a downward navigation. Oars and sails failing, some 
other means had to be tried ; the steam engine, then, just coming 
into use, was employed ; and from the fact that the same engine 
may be made to work at any speed, and almost with any power, 
its utility was at once established. We will now consider the 
obstacles to be overcome. 

100. In the first place, at certain seasons of the year the 
rivers are usually so low, as to have only three or four feet of 
water. 

Secondly, in some parts of the rivers the channel is so con- 
fined, as to render the current very rapid. 

Thirdly, in many parts the stream is so slight, as to be really 
of no importance. 

101. To overcome the first difficulty, it was necessary that 
the boat should draw very little water ; the second, that the 
engine should be very powerful ; the third, that the engine 
should be readily reduced from a greater to a lesser power ; for 
if it were not so, there would occur a very great waste of 
power or fuel, and consequently a very considerably increased 
and unnecessary expense. Such, then, being the obstacles, we 
will consider the means used to overcome them. 



STEAM NAVIGATION. 125 

102. The vessels are built to draw from two to four feet of 
water, and of such beam and length as the nature of their 
cargoes demand. The general dimensions are as follows ; 
namely, extreme length 150 feet ; breadth of beam 20 feet ; 
draught of water 3 feet. They are capable of accommodating 
from 200 to 400 passengers, besides carrying several hundred 
bales of cotton, and other goods. 

103. More expense has been incurred, and time and ability 
employed in bringing to perfection the model of these boats, 
than has probably been expended on any other kind of vessel 
in the United States. 

104. The engines are very strong and carefully made, al- 
though there is no great amount of bright work about them. 
They are placed either horizontally, or at an angle tending 
upwards to the centre of the paddle wheel shaft. 

105. The boilers are of small dimensions, but many in 
number ; they are nearly always cylindrical on account of 
their required strength, and also to save room ; and because 
when any increase or diminution of power is required, any 
one or two can be attached to, or detached from the engine 
at pleasure, by means of cocks and valves arranged for the 
purpose. 

106. The steam is used expansively, as being most econo- 
mical in every point of view ; and, in the methods adopted to 
do that most effectively, great ingenuity and skill have been 
manifested. 

107. The dangers to be apprehended in navigating these 
waters, of running aground, and meeting sudden shocks, have 
to be guarded against as much as possible ; the sudden stop- 
ping of the paddle wheel has to be expected, and to meet that 
circumstance, as well as for economy, the connecting rod is 
made of pine wood. 

108. From the enormous pressure at which the steam is 
used, the ordinary valves and methods of working them would 
absorb too much power, consequently a very simple and effect- 



126 STEAM NAVIGATION. 

ive arrangement has been introduced, by means of which it is 
rendered easy and rapid. 

109. As the quantity of water evaporated is very great, so 
is the quantity of fuel consumed great in proportion ; to save, 
therefore, as much as possible, the exhausted steam is suffered 
to escape through a copper vessel or chimney, called a " cough- 
ing box," where it deposits a portion of its caloric, which is 
taken up by the water for the feed, which surrounds it, and 
which is then passed on to the boiler. 

110. The speed of these boats varies from 8 to 15 miles an 
hour in ascending the rivers, and frequently, when going down 
to New-Orleans, nearly doubles the latter speed, the average 
being 18 miles. 

111. The actual occasion of the serious accidents which 
have occurred on these waters, is owing to three or more 
causes, of which we will place, 

First, the striking of snags or sawyers ; 2d, the insufficiency 
of the engines ; 3d, the fact of the captain having undisputed 
authority over the engine, and all connected therewith ; 4th, 
the inability of the boilers to bear the pressure that the caprice 
of the captain, or ignorance and neglect of the engineer charges 
them with. 

Divest these boats of the three last causes, and they would 
equal, if not surpass, in safety, any boats with low pressure or 
condensing engines in these or any other waters. 



CHAPTER IL 

PADDLE WHEELS. 

112. As the effective value of the marine steam engine is 
intimately connected with the form and dimensions of the 
paddle wheel, we purpose, in this part of the work, to say a 
few words on the subject. 

113. Notwithstanding the fact that the common paddle wheel 
was decidedly the first adaptation of any kind attached to vessels 
for the purpose of propelling them through the water (and 
from the close affinity existing between the old undershot water 
wheel and its performances, and the desired effect required in 
propelling vessels, it appears obvious that such should have 
been the case) ; nevertheless, engineers and speculators not 
only doubted the possibility of the common paddle being ef- 
fective, but actually laid it aside as altogether useless, because 
the steam engine itself was so inefficient as to be unable to 
cause the vessel to advance at all, except at such speeds as 
rendered the application of steam power to navigation altogether 
of no value. 

114. For such reasons, the paddle wheel was condemned 
as useless ; and the ingenuity of the curious was busily en- 
gaged in attempting to find out or adopt some other means for 
attaining the same end. 

115. An intelligent Frenchman copied the very beautiful 
action of the ' duck's foot,' collapsing when drawn forward, 
and expanding when pushed back. Another individual ap- 
plied paddles vertically to the sides of the vessel, acting 
similarly to those used by the Indian in propelling his canoe. 
Another had a series of float-boards attached to a beam, which 



128 STEAM NAVIGATION. 

were drawn through the water, raised, carried forward, de- 
pressed, and again drawn back. Again, the idea of driving 
water in at the bow of the vessel, and forcing it violently out 
at the stern, by means of a pump or pumps, occupied the pub- 
lic attention for some time ; this scheme was also soon aban- 
doned. Many other plans were successively tried, which it 
would be useless here to enumerate ; it must be acknowledged, 
however, to the credit of the inventors, that all these various 
contrivances performed their duty, but at a speed so slow as 
to be discarded and thrown aside nearly as soon as they were 
completed. 

116. There have been, however, one or two adaptations in- 
troduced within the last few years, which have attracted more 
attention than any of the former ones ; namely, the screw pro- 
peller, and the chain and drum. The former consists of a 
screw, similar to that ascribed to Archimedes, placed horizon- 
tally in a chamber in the bottom of the boat or vessel, which is 
caused to revolve by means of gearing worked by a steam 
engine, and so worms the water through it ; thus causing the 
vessel to advance without creating the back-water and undula- 
tions produced by the paddle wheel. The latter plan is to 
have a continuous chain laid along the bottom of the canal, 
which is passed round a drum on board the vessel, and again 
let down through a hawse pipe at the stern ; thus, upon the 
drum being caused to revolve, the vessel is drawn forward. 
These two plans, however, are more adapted for canal naviga- 
tion, where the undulation of the water which would be caused 
by the use of paddle wheels is so very injurious to the banks, 
than for any other kind of navigation, in which the paddle wheel 
is most certainly more efficacious than any other combination 
yet in operation. 

117. The revival of the paddle wheel, and consequently al- 
most the actual existence of the steamboat, at least at so early 
a date as it did come into use, was owing to the unprejudiced 
and energetic mind of the elder Stevens ; who, when trying his 
experiments, was requested by one of his men, to make use 



STEAM NAVIGATION. 129 

of a wheel similar to the common water wheel, which he, 
amongst the rest, imagined much too simple an apparatus to 
effect such a purpose. He did, however, try the plan, and as 
it certainly answered his views better than any other contri- 
vance, it was forthwith applied to boats by himself and others. 

118. The credit of this, however, still remains with the 
family ; and Mr. R. L. Stevens, one of the sons, has, within 
the last few years, considerably improved the paddle wheels ; 
which improvement is now in general use throughout the United 
States and elsewhere. It should here be remarked, that the 
steam engine has been considerably improved in the mean- 
time. 

119. The first wheel used was a simple wheel with buckets 
or float-boards, radiating from the centre, and extending across 
the whole width of the wheel, in a direction parallel to the shaft 
or axle. 

120. In the next, the floats were so arranged as to enter the 
water rather more at a right angle ; this plan was soon con- 
demned, as the wheel had a natural tendency to raise the water. 
The floats were again altered, and they were placed diagonally, 
instead of directly, across the width of the wheel. All these 
changes were for the purpose of obviating or removing, if possi- 
ble, the bad effects of the back water and wave caused by the 
common float, which materially retarded the speed of the vessel ; 
still the object was only partially gained. At this time, as before 
stated, Mr. R. L. Stevens applied his mind to remedy this evil, 
and he consequently introduced the split bucket, now so much 
used ; how far he succeeded in accomplishing his object may be 
readily seen, by observing the great difference between the 
action of his wheels and others on the old plan, upon the water. 

121. The paddle wheels of the new 'North America' are 
on this construction, (of which plate 27 represents one,) with 
the method of attaching the buckets or float-board. 

122. The subject of paddle wheels, and the desire to over- 
come the above mentioned objections to the use thereof, at least 
m their original form, has occupied no little of the time of Eu- 

17 



130 STEAM NAVIGATION. 

ropean engineers during the last few years. Many patents have 
consequently been taken out, for combinations tending to this 
desired end ; but, generally, the great expense attending their 
outfit, and very great liability to derangement, have confined 
their use to experimental vessels not adapted to ocean navi- 
gation. Morgan's patent paddle wheel, which is one of the 
best, has been successfully applied to some of the British 
steam vessels of war ; their expense, however, and their com- 
plication has deterred most materially their introduction into 
general use. 

123. It had now become obviously a great desideratum to 
arrange such a wheel as should obviate the original objection 
to paddle wheels, without incurring the objections to Morgan's 
wheel. Mr. Joshua Field, the celebrated English engineer, 
undertook, in consequence, a series of experiments on the com- 
parative value of different arrangements, into which he entered 
with great accuracy and care, and the result he has embodied 
in what he terms the "Cycloidal Paddle Wheel." Such is the 
wheel which he applied to the ' Great Western' steam ship, now 
trading between this port and Bristol, and which is also applied 
to the steam ship ' British Queen,' between London and this port. 
This wheel, for ocean navigation, bears superiority over all 
others ; as from its form it takes the water gradually, and, from 
the narrowness of each float-board, it lifts little or none; making, 
in consequence, a very small wave when compared to the old 
bucket wheel. 



PART IV. 



LOCOMOTION. 



LOCOMOTION. 

124. The application of steam to the purposes of locomo- 
tion has been attended with the most beneficial effects. Obsta- 
cles which, a short time ago, appeared insurmountable, have been 
overcome ; economy in construction and use has been studied, 
and speed and durability obtained. As a proof of this, we extract 
from a circular, published by Mr. W. Norris, of Philadelphia, 
the following letter, which shows that the monstrous amount of 
money expended in repairing the engines on the Manchester 
and Liverpool Rail- Way may be saved to the Company, whilst 
the amount of work done shall in no way decrease : 

Certificate. — " I have been in the employ of the State of 
Pennsylvania, as Locomotive Engineer, for nearly two years ; 
and had in my charge the locomotive ' Lafayette,' made by 
William Norris, for five months and three days. She performed 
regularly each and every day (except four days), with full 
trains, very frequently thirty-eight cars. This engine never 
lost a trip, and the whole cost of repairs for the five months and 
three days, did not amount to one dollar. 

" (Signed,) JOHN DONAHOE." 

125. When we look back, and examine the crude attempts 
of the mechanics thirty years ago, to adapt the power of steam 
to the purposes of locomotion, we are apt to smile ; but we 
should never for a moment forget, that it is to such individuals 
and their extraordinary exertions, that we owe the benefits we 
are now enjoying. Nor should the fact that these were chiefly 
self-taught men — men who had none of those advantages which 
are attainable now, by the poorest labourer as well as by the 
wealthiest merchant, the advantages of learning and education 
— men who had to earn their bread by the sweat of their brow, 



I 



134 LOCOMOTION. 

as well as try out their experiments. The veriest novice of the 
present day can converse fluently upon subjects that were then 
unknown, or if known, only to a very few ; and when any ac- 
count of these matters was promulgated, they came forth, not 
in the simple terms of common arithmetic, but dressed in the 
garb of algebraic formulas. These documents, to the plain 
mechanic, were consequently comparatively valueless ; and the 
only person, perhaps, able to judge and appreciate the value of 
the matter they contained, was debarred all access and acquaint- 
ance with it. 

126. We are glad to see that writers on scientific subjects are 
now reducing their formulae to such terms and expressions as 
are intelligible, not only to the learned of the earth, but to the 
simple ones, and the consequent advantages are becoming daily 
more apparent. 

127. For, how long did the notion prevail, that an engine 
was incapable of advancing on a rail-way, unless through the 
intervention of a wheel and rack, or propellers, which were to 
act like feet, at the back of the machine, and push it forward ? 
What numberless patents were taken out, and models made, 
showing the beauty and convenience of each arrangement? 
Could the gentleman who invented and patented the locomotive ' 
engine, which, to this day probably, brings its trains of coal 
wagons into the town of Leeds — and the extraordinary man 
who manufactured, and, in all human probability, arranged the 
machine — see the locomotive engines which have been sent out 
from the same shop within the last few years, — imagination 
may picture, but words cannot pourtray, their intense surprise, 
when, instead of the massive machine such as they devised, 
they see the comparatively light and fragile locomotive of the 
present day ; its four wheels turned and polished on their tires, 
as if the slightest roughness would retard its progress, and as 
capable of going fifty miles per hour with its load as at the 
slower speed of seven and a half ; which is the greatest, I be- 
lieve, that the old machine can perform with safety. 

128. Had Matthew Murray received the advantages now at- 



LOCOMOTION. 135 

tainable by every one, to what might not he have arrived ? The 
mind that was sufficient to apply the eccentric wheel and slide 
to the steam engine, if stored with the experiments and learning 
of the well educated and informed of other nations, might have 
arranged and built a machine such as we, with all our learning, 
have not been able yet to do. But to recur ; until accident 
stepped in and pointed out the connection between the gravity 
of the engine and the friction of the wheel on the rail, hardly 
any one believed in its existence. The philosophers of the 
day laughed at it ; argued and experimentalized on the subject, 
and the fact was nearly being committed to the storehouse of 
nature, to be preserved for another generation w r ho might pos- 
sess clearer perception than ourselves. Such, however, was 
not the fact. It was received with jealousy and doubt at first, 
we must admit ; nay, it is at the present day looked on with 
suspicion, though we have such facts as the following to prove 
its truth : 

129. The steam engine ' George Washington,' made by 
Norris, of Philadelphia, ascended an inclined plane with a rise 
of one foot in fourteen, with a load of 19,200 lbs., at the rate 
of fifteen and a half miles an hour ; the engine weighing 
14,930 lbs. only. 

130. This, it must be remembered, was not the result of for- 
tuitous circumstances, but what the engine could perform during 
a week as well as during the two minutes and one second she 
was about it. The steam was 60 lbs. on the inch. This fact 
was witnessed by numbers of gentlemen, who can all give evi- 
dence of its truth. Here, then, is rather a severe blow to the 
philosophers. But here is also a proof of the benefits arising 
from a knowledge of cause and effect ; the result of which is 
the fact that, where the engine is so arranged as to have as 
much weight as possible on the driving wheels without increas- 
ing the actual weight of the machine, the best effect is pro- 
duced. But these facts, as well as hundreds more, were hid- 
den from our elder brethren of the profession ; it becomes us, 
therefore, not to see them now overlooked, 



136 LOCOMOTION. 

131. The great advantage which results from rapid com- 
munication has called into operation the inventive talents of all 
nations. The science of mechanics is not now as firmly con- 
fined to the classes who gain their bread by its pursuit, but is 
followed up with ardour and enthusiasm by men of education, 
ability and wealth. So far has the benefit of its study pro- 
gressed, that any one ignorant of its principles and rules is 
hardly considered to have received a liberal education. And 
to what result does this study of mechanics — some sceptic may 
advance — to what good does it tend ? We answer boldly, to 
the benefit of the whole human family ; in the increase of 
wealth, happiness and comfort. 

132. The man of leisure, instead of wasting his time in 
idleness, now occupies himself in trying to improve what has 
been already done, or in inventing new methods for obtaining 
the same ends. And, whilst the mechanic is toiling at his 
bench, he is in study, arranging and scheming new work for 
him. It is to such men as these that a country is indebted. 
More is due to such men as Stevens, Fulton, and Evans, 
than is recorded as having been paid to the Roman generals 
on their return from a successful campaign. Time and wealth 
have been disregarded in making our steamboats and rail- 
roads, the most convenient and speedy in the world ; pri- 
vate and temporary interest have been set aside for public good, 
and the permanent benefit to all is large. 

133. The first successful manufacturer of locomotive en- 
gines in the United States was Mr. M. W. Baldwin, of Phila- 
delphia ; who, about the year 1829, commenced by making a 
small model of an engine, not very unlike the arrangement of 
Messrs. Braithwaite and Erickson's engine, the ' Novelty,' 
which so ably contested with Mr. Stephenson's engine for the 
prize, on the Manchester and Liverpool Rail- Way, on its first 
opening. 

134. Soon after this, Mr. Baldwin constructed the first loco- 
motive for the Germantown and Philadelphia Rail-Road, now 
called the ' Old Ironsides,' which engine was the first (having 



LOCOMOTION. 137 

her cylinders on the outside of the smoke-box) that had been 
manufactured in the United States. This circumstance, at the 
time, caused much ridicule and many remarks to be passed on 
the manufacturer. Time, however, has abundantly proved the 
folly c f those persons, and the correct views of Mr. Baldwin ; 
all manufacturers having since that time placed their cylinders 
outside — thus copying the very plan they had formerly derided. 

135. About this time a locomotive engine was sent from the 
West Point foundry for the same road, which was not success- 
ful. Some engines were also sent from the same place to 
the Mohawk Rail-Road, which, after being altered by Mr. 
David Matthews, answered very well. 

136. A difficulty now occurred which threatened to injure 
the benefits arising from travelling by steam, if not to remove 
them altogether, namely : the engines which had been imported 
were, from the complicated form of their working parts, the 
number of bearings which occurred, and their consequent lia- 
bility to get out of repair, nearly all very soon out of 
working order. This occurred in a measure from the nature of 
the roads, and from the curves on the line being in many 
cases of such short radii, that the engines on four wheels could 
not work round them without actually jumping, at every 
yard or so, from the flange of the front wheel riding on 
the rail. This circumstance attracting the attention of Mr. 
David Matthews, he immediately suggested and applied the 
truck frame, which is attached to the locomotive engines, (plates 
43, 47, 48,) which, moving on a centre pin, and the wheels 
not being far apart, suits itself to any curve that may occur ; 
thus enabling the engines to go round without any danger or 
difficulty. So beneficial is this arrangement of Mr. Matthews, 
that the English manufacturers are now using it, affording am- 
ple proof of its efficacy. 

137. From this time, Mr. Baldwin and some others were 
carrying on a very extensive trade in the manufacture of loco- 
motive engines, in supplying the rail-roads throughout the* 
Union as fast as they were prepared to use them. Their great 

18 



138 LOCOMOTION. 

success induced Mr. Norris, of Philadelphia, to embark in the 
same business, he being very anxious that our machines should 
equal, if not surpass, the English engines in their perform- 
ances. To this end, he advanced a considerable sum of money 
to assist Col. Long, of the U. S. Engineers, in his project of 
building a locomotive engine. 

138. The first attempt had a boiler shaped in front like the 
bows of a boat, to enable it to cut through the air with less 
difficulty than if the end had been flat, as they are made at 
present ; the boiler had two return flues. The cylinders and 
other parts were sufficiently effective, but the boiler was a com- 
plete failure ; the gentleman not being so familiar with civil 
engineering as to know that on the efficacy of the boiler de- 
pends almost entirely the value of the working power of the 
engine. 

139. After spending much time and money in trying experi- 
ments, and projecting new ideas, he finally abandoned the un- 
dertaking, having fully satisfied himself and Mr. Norris of his 
inability to perform the task. Mr. Norris, however, though 
much disappointed, and nearly exhausted as to pecuniary means, 
still persevered, and by good fortune, meeting with Mr. F. D. 
Sanno, an intelligent and clear-headed mechanic, forthwith en- 
gaged his services. 

140. Mr. Sanno, being sensible of the necessary provisions 
for such a machine, set to work and made a new boiler ; he 
however used the old cylinders, and some other parts, and final- 
ly turned out a new machine. With this engine, Mr. Sanno 
had often boasted that he would ascend the Columbia inclined 
plane on the Pennsylvania State Road, a few miles from Phila- 
delphia ; and this assertion he made long before he had finished 
the engine. He was of course openly laughed at ; but, as in 
a former case, the ridicule returned on the heads of those who 
sent it. For, one morning in the month of July, 1 836, the first 
trial that had been made with the engine, Mr. Sanno, and two or 
.three of the workmen, got the steam up, and proceeded from 
Mr. Norris' works to the top of the inclined plane, which they 
ascended without hindrance or difficulty. 



LOCOMOTION. 139 

141. Mr. Norris having thus established a name for the 
manufacture of locomotive engines, soon had his shops full of 
work ; and, under the careful superintendence of Mr. Sanno, 
he is certain to meet with that success his enterprising conduct 
so justly deserves. 

142. During the year 1839, the regular delivery was one 
locomotive engine per week ; an amount of work which ex- 
ceeds that of any other establishment in the United States. 

143. Many very beautiful and effective engines have been 
made since Mr» Baldwin commenced, far exceeding in their 
power and economy the utmost expectations of their inventors, 
amongst whom are Messrs. Rogers, Ketchum, and Grosvenor, 
of Paterson, New- Jersey ; Messrs. Harrison and Eastwick, of 
Philadelphia ; Dunham, of New- York, and many others. 

144. In considering the power and arrangement of a locomo- 
tive steam engine, we shall have to take into account a circum- 
stance which does not enter into the calculations for a land en- 
gine — that is to say, weight ; for, as upon its weight and the 
arrangement thereof, the power of the engine materially rests, 
it will be well to consider this subject a little maturely before 
entering into the detail of the engine. 

145. Locomotive engines have four, six, or eight wheels ; 
two or more of which are attached to the engine. Each one of 
these wheels may sustain an equal portion of the entire weight, 
or two may be made to bear the greater part, and the weight 
may then be divided amongst the rest. 

146. It is well known that if a weight W be suspended from 
a point C, on a bar A B, which is equidistant from A and B, 
A C B_ half of the weight will be sustained 

o "W at A, and the balance at B ; but if 

the weight W be moved, as shown below, to another point D, 
which is one quarter of the whole length from B, then B 

A. D B will sustain three parts, and A only 

<i> W one. Supposing, therefore, that the 

line A B represents the frame of a locomotive steam engine, 
every alteration in the position of the wheels will mak e a cor" 



140 LOCOMOTION. 

responding alteration in the effective power of the machine ; 
for consequent upon its weight is the adhesion of the wheels to 
the rails. The skilful adjustment of this weight seems to 
have escaped the earlier manufacturers of locomotives. The 
great attention which this circumstance now receives, has pro- 
duced such machines as the one already alluded to. Having 
thus seen the effect the weight exerts, we will proceed to other 
matters. First in importance, therefore, is the boiler, its form, 
capacity, and generating surface. 

147. Pambour, in his work on Locomotion, says that the pres- 
ent form of boiler belongs to a French gentleman, of the name 
of Seguin. It matters little to us who was the real inventor, 
though at the same time we are desirous of awarding to each 
his due. Therefore, whether William Booth or Seguin invent- 
ed the same, we certainly use it, and are fully sensible of its 
decided superiority over every other arrangement for the same 
purpose. 

148. Fire Boxes. — The size and extent of the fire boxes is 
another circumstance to be considered ; no decisive rule, how- 
ever, having been yet given, we can only set before the reader 
statements of the dimensions of the various locomotives which 
we have examined ; and from these facts he will be enabled to 
deduce such dimensions as will correspond to the arrangements 
which produce the best effects. 

149. For Table of Dimensions of Fire-Boxes, §c. see the 
end of this work. 

150. Tubes. Upon the number of tubes in the boiler much 
of its power depends ; the greater the number of tubes, the 
greater surface of water will be exposed to the action of the 
fire. In the American engines, a greater number of tubes are 
used than in the European ; this circumstance alone gives us 
an advantage. 

151. Chimney. — The dimensions of the chimney should be 
considered in connexion with the area of fire grate, and the 
quality of fuel used. The chimnies of some locomotives im- 



LOCOMOTION. 141 

ported from England have been reduced from 14 to 10 inches 
diameter, and with good effect. 

152. Fire Grate. — Upon the area of fire grate and generating 
surface, the capabilities of the boiler depend ; and if the boiler 
cannot supply considerably more steam than is required, the 
least extraordinary exertion will prove its inefficacy ; the 
dimensions, therefore, or capacity of the cylinder must be con- 
sidered, in estimating the number of tubes and area of generating 
surface, as well as the area of grate. 

153. Blast Pipe. — The arrangement of the blast pipe, as 
regards its admission into the chimney, is another point to 
which attention must be called ; for upon its position will de- 
pend the value of the application. We have found by expe- 
rience, that the higher the pipe is carried up the chimney, the 
less the power of the draught, and also that any openings in 
the smoke box are very objectionable. The blast pipe is now 
admitted only half an inch above the top of the smoke box, and 
the increase of draught is found to be very great in consequence. 

154. Cylinders. — The cylinders are fixed to the outside of 
the smoke box, and are placed at an angle suited to the dimen- 
sions of the driving wheels. The difference between these 
and the English consist in our ports or steam openings being 
larger, and our waste or eduction passage less cramped. 

155. Valve. — The valves are much the same, only their 
capacity for the egress of steam is greater. 

156. Valve Rods. — Instead of the complicated machinery 
which occurs in Stephenson's patent locomotive, and which 
from its confined position is difficult of access, the eccentrics 
are placed outside the frame. (See the plate of the locomotive 
* Juno.') The tumbling shaft is attached to the under side of 
the frame, and from the eccentric to the slide only three pins 
occur where the motion is changed. The handle raises the 
one eccentric rod and drops the other. 

157. Connecting Rod. — The connecting rods, instead of be- 
ing 36 or only 42 inches long, are produced to 8 feet 2 inches, 
which not only reduces the friction on the guides most materially, 



142 locomotion/ 

but also naturally alters the position of the driving wheels, and 
enables us to have as much as possible of the whole weight on 
them. 

15S. Safety Valve. — The position of the safety valve over 
the throttle valve, though it does not affect the working of the 
engine, materially lessens the liability to accident, by indicating 
more clearly the pressure of the steam, from the circumstance 
of its being received from too close a proximity to the surface 
of water in the boiler. 

159. General arrangement. — By this system of arrange- 
ment, greater care can be bestowed on the strength and dimen- 
sions of the working parts ; and in case of accident, as every 
part is in sight, it can immediately be attended to. The in- 
creased economy of our engines over those of English manu- 
facture is obvious, when the expense of repairs is taken into 
consideration — many of the engines working for months without 
requiring the expenditure of a single dollar. 

160. These engines are as well calculated for speed as the 
others, although the roads upon which they run are perhaps not 
so perfect in their construction ; and it is a source of pride to 
us to feel, that we have equalled, if not surpassed our master in 
his own peculiar province. 

161. The Slide. — One of the most important subjects for 
consideration, in estimating the value of a locomotive engine, 
as regards its tendency to increase or diminish speed, is the 
slide, upon the lead of which much depends. In engines such 
as were at first imported from England, the lead was invariably 
on the steam side, varying from one to five-eighths ; and this 
plan has been in use here until very lately. The advantage 
gained by the different degrees of lead with certain loads is 
subjoined in a tabular form, to enable the engineer to decide 
at once upon what lead will suit his work best. 



LOCOMOTION. 



143 



Practical Table of Gain in Speed by various degrees of 
Lead of the Slide. 





^ to 


Velocity in miles per hour, the 


Particulars of Engine. 


JJ 


lead of the valve being 


o.s 





i 


I 


f 




tons. 


miles. 


miles. 


miles. 


miles. 


Diam. ofcylind., 11 inches, 


50 


31.02 


31.52 


32.51 


34.23 


Stroke, 16 inches, 


100 


21.68 


22.02 


22.72 


23.92 


Wheels, 5 feet, 


141 


17.39 


17.66 


18.22 


19.18 


Effective pressure, 50 lbs., 


155 


16.28 


16.54 


17.06 


0. 


per square inch. 


163 


15.72 


15.96 


0. 


0. 




165 


15.58 


0. 


0. 


0. 




50 


27.80 


28.24 


29.13 


30.68 


Diam. ofcylind., 12 inches, 


100 


20.05 


20.37 


21.01 


22.12 


Stroke, 16 inches, 


150 


15.68 


15.93 


16.43 


17.30 


Wheels, 5 [eet, 


168 


14.56 


14.79 


15.25 


16.06 


Effective pressure, 50 lbs. 


183 


13.72 


13.94 


14.38 


0. 


per square inch. 


193 


13.22 


13.43 


0. 


0. 




196 


13.11 


0. 


0. 


0. 




50 


26.16 


26.57 


27.41 


28.86 


Diam. ofcylind., 12 inches, 


100 


19.85 


20.16 


20.80 


21.90 


Stroke, 18 inches, 


150 


15.99 


16.24 


16.75 


17.64 


Wheels, 5 feet, 


188 


13.93 


14.15 


14.60 


15.37 


Effective pressure, 50 lbs. 


207 


13.09 


13.30 


1372 


0. 


per square inch. 


217 


12.69 


12.89 


0. 


0. 




221 


12.53 


0. 


0. 


0. 



The above table is extracted from Pambour's " Experiments 
on Locomotive Engines." 

Thus, then, it is evident that too great a lead detracts from 
the power of the engine ; care must therefore be taken not to 
exceed certain limits. 

The lap or cover of the valve, is another matter to be con- 
sidered ; it is a certain excess of face on the steam side more 
than the steam opening for the purpose of cutting off the steam 
at any desired portion of the stroke. 

The practice, as stated above, was followed nearly by all 
engineers until very lately, when it was discovered, that by 



144 



LOCOMOTION. 




giving a lead to the exhaust, a very increased effect was obtain- 
ed ; upon trying the experiment again, the result was equally 
satisfactory, in consequence of which the old slide has been 
removed and a new one substituted in several instances. The 
following diagrams will more fully show the extent of lead and 
manner of adjustment. 

DlAG. A 

A A, the face of the 

valve. 
B, the slide. 
C C, the steam- 
ways. 
D, the exhaust open- 
ing. 

In this diagram, the piston is at the top stroke, and conse- 
quently the steam is passing out in the direction of the arrow 
through C and D ; the lap of the valve over C shows the 
amount of cut-off of the slide ; the projection of the inside of 
the face of the slide is not found to be at all objectionable, 
which is decidedly a fortunate circumstance, as the requisite 
lead cannot be obtained without it. 

DlAG. B. 

shows the slide at 
the half stroke ; the 
two steam-ways are 
shut, and the ex- 
haust alone open ; 
here then arises the 
benefit : upon the slide moving in the direction of the arrow, 
the exhaust is opening, and the elastic force of the confined 
steam instantly causes it to escape, in a great measure, before 
the new steam, of a greater elasticity, enters the other end 
of the cylinder, and thus prevents that forcing which other- 
wise takes place, from the circumstance of the fresh supply 
having a greater velocity than that already used. 




LOCOMOTION. 



145 




DlAG. C. 

In this diagram, 
the piston is at the 
bottom stroke ; the 
arrows denote the 
direction of the 
steam and exhaust 
currents. The let- 
ters refer to the same parts in each diagram. 

Facility in reversing the motion has long been a very great 
desideratum, and many very ingenious arrangements have been 
executed, all of which answer the purpose with greater or less 
effect ; but none of them seem to have given complete satis- 
faction. The annexed diagrams will explain a method used 
and invented by that ingenious mechanic, Mr. Harrison, of 
Philadelphia. 

DlAG. D 




represents a section of the valve-box, slide, and reversing face ; 
A and B the steam-ways ; C, the exhaust passage ; D, the 
slide ; E E, the reversing face ; F, the face of the valve ; G, 
the face of the reversing face ; H, the valve-box ; K K, ordinary 
steam openings. 

In this position, the engine is going forward ; the steam 
entering the cylinder at B, and exhausting from A ; the slide 
D being a simple slide made according to the old rule. 

In this case, therefore, or when the engine is advancing, the 
action is merely that of a common slide. 
19 



146 



LOCOMOTION. 

Diag. E 




is a plan of the slide and reversing face, showing the steam 
passages on each side at c' c ; this is the plan of the arrange- 
ment exhibited above. 



Diag. F. 




Here the face is reversed ; that is, the ordinary steam open- 
ing K' in the reversing face, by moving the reversing face, is 
brought over the exhaust C, and the other opening K is closed 
by being brought over the valve face ; the slide D remaining 
in the same position, the action is as follows : — The steam 



LOCOMOTION. 147 

passes from the boiler through a, along the passage a', through 
the opening a", into the steam-way A, whence it acts upon 
the piston ; in like manner the exhaust steam passes from the 
steam-way B into the opening b, along the passage b', into the 
opening b'', whence it escapes into the exhaust C. Thus the 
operation of reversing is performed instantly, and without any 
trouble ; the only danger is in the engineer reversing too sud- 
denly under high speed. 

162. Locomotive Engines. Although the usual rule for 
calculating the power of the steam engine (page 161,) is suf- 
ficiently well adapted to fixed and marine engines, it will be 
seen that it is altogether inapplicable to locomotive engines — 
and for the following reasons : — 

1st. According to the generative power of the engine. 

2d. According to the ratio of speed between the piston 
and periphery of the driving wheel. 

3d. The speed or velocity of the piston varies according 
to the load to be convey d. 

4th. According to the pressure on the piston ; and 

5th. According to the plane of the road. 

163. In land or fixed engines, we have a certain speed, to 
secure which we apply the governor, and the slightest varia- 
tion is corrected ; thus adapting the supply of steam to suit 
the load. We also apply the vacuum gauge, and ascertain ex- 
actly what the pressure on the piston actually is ; consequently, 
the rule holds good. 

164. In marine engines we estimate the power, knowing the 
speed of the boat through the water, and its actual resistance 
at such speed. 

165. (1st.) In the locomotive engine we have no constant 
numbers but the friction per ton, and that varies very con- 
siderably — differing, more or less, through every foot of rail 
passed over, and for each variety of carriage — hence, to settle 
the power of the engine, we must ascertain the areas of sur- 
faces exposed to the radiation and in contact with the flame, 
together with the area of fire grate, and quantity of fuel in 



148 LOCOMOTION. 

fire box. To enable the reader, at a glance, to see the surfaces 
exposed in different engines, we subjoin the following table ; for 
the sake of comparison, we also insert two of the best En- 
glish Locomotives, as detailed by Count Pambour, in his 
" Treatise on Locomotion." 

166. For Table, fyc, see the end of the ivork. 

167. The facts deduced from the table are therefore as fol- 
lows — viz. That it requires an area of about 38 square feet to 
be exposed to the radiating action of heat, 375 square feet to 
contact, 7.33 feet of fire-grate, and 22.33 cubic feet of fuel, to 
enable a locomotive engine of the usual construction to perform 
well. 

168. (2d,) The length of stroke, and the diameter of the 
driving wheel are given ; the ratio will be the proportion that 
twice the length of stroke bears to the circumference of the 
wheel. 

169. (3d,) The velocity of the piston varies according to the 
load to be conveyed. The weight of the engine and the ef- 
fective pressure being the same, the velocity of the piston will 
be affected by any addition or diminution of load ; for an 
engine will not draw 200 tons at the rate of 25 miles per 
hour, if its utmost power is 150. 

168. (4th,) Again, the velocity of the piston varies with the 
effective pressure ; if 50 lbs. per square inch enables an engine 
to draw 150 tons at 25 miles per hour, the friction, or adhe- 
sion of the driving wheels to the rails remaining exactly the 
same, 40 lbs. will not be sufficient to do the same, as it will not 
exert a power on the piston great enough to overcome the re- 
sistance of the train. 

169. (5th,) The piston is again subject to another obstacle, 
which materially affects its speed, namely, the plane of the 
road — for, in ascending a plane, however trifling the grade, an 
increase of power is absolutely indispensable ; — thus the engine 
which can draw 150 tons at 25 miles on a level, can only draw, 
say 75, upon an inclined plane ; the balance of the 150 being 
absorbed in overcoming the extra resistance of the engine itself, 



LOCOMOTION. 149 

as well as of the whole train. Having premised thus much, 
on reference to the table (which will be found at the end of 
this volume), the working parts of the different engines will be 
seen at a glance. 

171. Upon consideration it will be seen, that although 50 lbs. 
may be the effective pressure of the steam, it does not follow, 
as a matter of course, that by taking away a considerable part 
of the load, a proportionate increase of speed will be attained, 
— for this depends not upon the pressure, but upon the genera- 
tive power of the boiler ; for instance, the engine that can convey 
150 tons on a level, at the rate of 25 miles an hour, may not be 
enabled to move even itself at the rate of 50, for although its 
generative power be equal to 1864 cylinders of steam per hour, 
yet it has not power to double that supply, or to increase it at 
all at the same rate, that is, in the same time — hence it becomes 
necessary to keep these facts in mind during the following 
calculations. 

172. From experiments by Pambour, it appears, that the 
power requisite to draw one ton weight on a level amounted to 
8 lbs. 

173. Practical Rules for calculating the power of Loco- 
motive Engines. Before entering into any calculations, we 
here subjoin the value of the signs made use of, in the follow- 
ing formulae. 

174. m = The gross load in tons. 

M The gross load in pounds. 

n = The resistance per ton, or 8 lbs. per ton. 

c = The rise of unity in proportion to the length of 

the plane. 
R = The resistance of the periphery of the driving 

wheel. 
D =*= The diameter of the driving wheel in inches. 
a = The diameter of the cylinder in inches. 
I = The length of the stroke in inches. 
f = The friction of the engine. 
p = The atmospheric pressure. 
P = The pressure per square inch on the piston. 



150 LOCOMOTION. 

H = The horse power. 

C = The constant number, which is explained in 

Rule VI. 
V = The velocity of the engine. 
175. Rule 1. To find the resistance to traction on the pe- 
riphery of the driving wheel. 

Multiply the gross load, expressed in tons, by 8, and the 
product will be the resistance on a dead level. 
Example. The engine 'Uncle Sam,' weighs 
10.5 Tons. 
Tender, . 7.0 " 
Tram, . . 100.0 " 



117.5 

8 



940.0 Traction on a dead level ; 
or, by formula, m n, or 8 m. 

176. Rule 2. To find the effective force of gravity, when 
the engine and train are running on an inclined plane. 

Divide the gross load in lbs. by the length of the plane 
corresponding to an ascent or descent of unity, the quotient 
will be the force in lbs. acting down the plane. 

'Example. The engine, tender, and train, weigh, as above, 
117.5 tons, which, multiplied by 2240, equals 263,200 lbs. 
The plane equals a rise of 1 in 128, and 

128)263,200.00(2056.25 lbs. the effect of gravity. 
256 

720 
640 

800 

768 

320 
256 

640 



LOCOMOTION. 151 

M 

or, by formula, — = effect of gravity. 

For ascending an inclined plane, the effect of gravity, as 
above, must be added to the traction on a level ; and descend- 
ing, must be subtracted. 

Thus, if the engine and train be ascending an incline of 1 
in 128, we have per last rule, 

Effect of gravity, 2056.25 lbs. 
Traction on level, 940. 



Which give 2996.25 lbs. traction up the 

M 

plane ; or, by formula for ascending, m n -\ 



M 

or 8 m H 

c 



for descending, m n 

& c 

M 

or 8 m 

c 

177. Rule 3. To find the whole force or resistance to be 
overcome by the engine. 

Determine the resistance to traction, by Rule 1 ; add to it 
one-eighth part, for the additional friction it causes on the en- 
gine, and 6 lbs. per ton of the weight of the engine for its own 
friction ; the sum will express the whole force or resistance to 
be overcome by the engine. 

Thus by formula, 9 m +/ = R. 

178. Rule 4. To find the effective pressure on the piston in 
lbs. per square inch. 

Multiply the resistance at the circumference of the wheel by 
its diameter in inches, and then divide by the product of the 
square of the diameter of the cylinder into the stroke. The 
quotient will express the pressure in lbs. per square inch on 
the piston, and add'ng 14.7 lbs. for the pressure of the at- 
mosphere, the result will be the effective pressure in lbs. per 
square inch on the piston. 

Example. The weight of the engine is 10.5 tons, the tender, 



152 LOCOMOTION. 

7 tons, the train, 50 tons ; the diameter of the driving wheels, 
54 inches ; the diameter of the cylinders, 1 1 inches ; and the 
length of stroke, 18 inches. It is required to find the pressure 
of steam in the cylinder to sustain an uniform velocity up an 
incline of 1 in 140. 

Engine weighs . . . . 10.5 tons. 
Tender " .... 7.0 " 
Train " .... 50.0 " 



Gross load, " .... 67.5 

8 



Hor. trpct., "..... 540.0 lbs. 
Gross load, 67.5 
2240 

27000 
1350 
1350 



140)151200.0(1080.1bs. effect of gravity. 
140 



1120 
1120 

Effect of gravity, 1080 

Horizontal traction, 540 

Inclined traction, 1620 lbs. 

1620 

Additional friction, 202.5 = ■ ft 

Friction of engine, 63. at 6 lbs. per ton. 



Resistance, 


1885.5 


Diameter of wheel 


, 54. 




75420 




94275 



101817.0 



LOCOMOTION. 153 

Diameter of cylinder, ll. 2 inches, x length of stroke, 18. 
II. 3 X 18 = 2178 
2178)101817.0(46.74 lbs. pressure on piston. 

8712 

14697 
13068 



16290 
15246 



10440 



46.74 
14.7 



61.44 lbs. effective pressure of steam required ; 

/9M „\ 

_ + 9m+/ j D 

or, by formula, thus, — \- p = P. 

179. Rule 5. To determine the power of a locomotive 
engine. 

Find the resistance by Rule 4, and then the power by rule, 
as follows : multiply the resistance by 8 times the velocity in 
miles per hour, and divide by 3.000, the result will express the 
horses' power. 

Example. Take the last case, and suppose the velocity to 
be 12 miles per hour. 

The resistance is, . . . 1885.5 lbs. 
12 X 8 = speed, . . 96. 



113130 
169695 



3.000)181008.0 



60.336 horse power. 

Or, by formula—^- = H. 
20 



154 LOCOMOTION. 

The power of a locomotive engine being known, it is required 
to determine the speed under any given circumstances of load, 
inclination of railway, &c. 

180. Rule 6. Find the whole resistance to be overcome ; 
multiply the number of horses' power by 375, and the product 
will be a constant number, to be divided by the resistance, to 
obtain the velocity in miles per hour. 

Example 1. Taking the foregoing case. 
Horse power, = 60.33 
375 



30165 
42231 
18099 

Constant number, 22623.75 
The resistance is 1885.5, then 

1885.5)22623.75(11.99 miles per hour. 

1885.5 



37687 

18855 

188325 
169695 

186300 
169695 



Q 

or, by formula, 375 H = C and-^ = V. 

For the velocity when the railway is horizontal, we have 
Horizontal traction, 540 lbs. 
Additional friction, 67.5 
Friction of engine, 63. 

Resistance, . . 670.5 lbs. 



LOCOMOTION. 155 

and 670.5)22623.75(33.74 miles per hour. 
20115 



25087 
20115 

49725 
46935 



27900 
26820 

1080 

The force arising from gravity being greater than the hori- 
zontal traction, in this example, the carriages would, of them- 
selves, run down the inclined plane, with an accelerated 
velocity ; and this would occur in all cases, where the inclina- 
tion is greater than 1 in 280. 

Example 2. To find the greatest uniform velocity of the 

same engine and train, down an inclination of 1 in 600. 

Horizontal traction, 540 lbs. 

67.5 X 2240 lbs. 

— — = 252 effect of gravity. 

Inclined traction down the plane, 288 lbs. 
Additional friction, . . . . 36 
Friction of engine, .... 63 

Resistance, 387 lbs. 

and 387)22623.75(58.45 miles per hour. 
1935 



3273 
3096 

1777 
1548 



2295 
1935 



156 LOCOMOTION. 

The velocity by rule would therefore be about 58 miles per 
hour ; but this is more than would occur in practice, owing to 
the imperfect state of the road and the resistance offered by 
the atmosphere, which from experiments long since made, we 
know exerts a pressure of .915 lbs. per square foot of surface 
at the rate of 20 miles an hour. 

181. For any particular engine, the constant number, which 
forms the dividend, when once found, will be ready for any 
particular application. 

In the calculation of the average speed, the distances tra- 
versed, or the time of transit, care should be taken not to over- 
look the circumstance, that nearly one half of the distances 
passed over in the gradual production and annihilation of velo- 
cities may be considered lost. 

182. By means of the foregoing rules, the mechanic will 
readily be enabled to calculate what any engine is doing, or 
what any proposed engine can do ; the velocities of transit, 
pressure of steam, and weight of train being fixed upon ; 
or inversely, having a certain weight to be moved, he can 
ascertain the power and weight necessary to convey the 
same. 

183. For those however, who are familiar with the applica- 
tion of Algebraic formulae, we here subjoin a synoptical table 
from the foregoing rules. 

1. The power of a locomotive engine being known, it is 
required to determine the speed under any given circumstances, 
of load, inclination of railway, &c. 

C 

/Q~M " — \ = V tne s P ee d or velocity. 

(^L + 9m+f ) 

2. To find the resistance or load, the velocity and power 
being given. 

3. To find the pressure of steam required in the cylinder, 
the load and inclination of road being given. 



LOCOMOTION. 157 

/_ + 9m+/ \ D 

-— — + p = P pressure per inch. 

4. The maximum, load an engine is able to draw at a de- 
termined pressure. 

(P—p)d*l . . ■ . , 
^r = the maximum lead. 

5. The pressure, load, and diameter of driving wheel given, 
to find diameter of the cylinder. 



6. To find the power of the engine. 

— = H the horse power. 



3.000 

7. To find a constant number to be divided by the resistance, 
which shall give the velocity with the maximum load. 
C = Hx 375. 



PART V, 



PRACTICAL RULES. 



RULES 

FOR CALCULATING THE POWER AND WORKING PARTS OF A 
STEAM ENGINE. 

184. To find the power of steam engine. The standard 
being 33000 lbs. raised one foot high per minute, or 150 lbs. 
raised 220 feet in the same time, which effect is equal to one 
horse power. 

Multiply the pressure per square inch by the area of the 
piston, that product by the velocity in feet per minute, and 
divide by 33000 lbs., the quotient is the number of horses' 
power. 

185. There are, however, two other circumstances to be 
taken into consideration ; namely, the friction of the engine, and 
the expansion of the steam. 

The friction in a high pressure non-condensing engine, will, 
with the atmospheric pressure, average 18 lbs. per square inch 
on the piston. In condensing engines, however, the case is 
different ; with an average vacuum of 27 inches, the atmo- 
spheric pressure being 14.7, or = 30 inches of mercury, we 
have 30 : 14.7 : : 27 : 13.23 ; and 15 — 13.23 = 1.77, to which 
must be added for the friction and inertia of the engine 8 lbs. : 
thus making a total of 9.77 lbs. per square inch on the piston. 

The next consideration is the expansion of the steam when 
cut off at any portion of the stroke, and the rule for finding the 
mean effective pressure is as follows : 

186. Divide the length of the stroke in inches by the distance 
in inches the piston has moved beforethe steam is cut off, and 
divide the whole pressure on a square inch of the piston in lbs. 
by the quotient. Add 1 to the hyperbolic logarithm . of the 

21 



162 



RULES FOR CALCULATING. 



number of times the steam is expanded, and multiply the lo- 
garithm by the number of lbs. to which the steam is expanded, 
and the product is the uniform force of the steam. 

TABLE XV. — Hyperbolic Logarithms. 



6 


Log. 


6 


Log. 


6 


Log. 


6 


Log. 


ii 


.2231435 


5f 


1.7491998 


15 


2.7080502 


33 


3.4965075 


i* 


.4054651 


6 


1.7917594 


16 


2.7725887 


34 


3.5263605 


if 


.5596157 


«i 


1.8325814 


17 


2.8332133 


35 


3.5553480 


2 


.6931472 


6* 


1.8718021 


18 


2.8903717 


36 


3.5835189 


n 


.8109302 


6J 


1.9095425 


19 


2.9444389 


37 


3.6109179 


24 


.9162907 


7 


1.9459101 


2C 


2.9957322 


38 


3.6375861 


n 


1.0116008 


74 


1.9810014 


21 


3.0445224 


39 


3.6635616 


3 


1.0986123 


7* 


2.0149030 


22 


3.0910424 


40 


3.6888794 


n 


1.1186549 


7| 


2.0476928 


23 


3.1354942 


41 


3.7135720 


H 


1.2527629 


8 


2.0794415 


24 


3.1780538 


42 


3.7376996 


3| 


1.3217558 


8| 


2.1400661 


25 


3.2188758 


43 


3.7612001 


4 


1.3862943 


9 


2.1972245 


26 


3.2580965 


44 


3.7841896 


4* 


1.4469189 


9* 


2.2512917 


27 


3.2958368 


45 


3.8066624 


4* 


1.5040774 


10 


2.3025851 


28 


3.3322045 


46 


3.8286414 


4| 


1.5581446 


11 


2.3978952 


29 


3.367295£ 


17 


3.8501476 


5 


1.6094379 


12 


2.4849066 


30 


3.4011973 


18 


3.8712010 


5* 


1.6582280 


13 


2.5649493 


31 


3.4339872 


49 


3.8918203 


5i 


1.7047481 


14 


2.6390573 


32 


3.4657359 5C 


3.9120230 



To convert common logarithms into hyperbolic, multiply the 
former by 2.3026. 

188. Before proceeding with the calculations, we subjoin the 
value of the several signs made use of. 

d represents the diameter of the cylinder. 



a i 


the area of the cylinder. 


I 


the length of the stroke in inches. 


V 


the length of cut-ofT in inches. 


P 


' the pressure in the boiler. 


P 


the atmospheric pressure. 


x l 


the uniform pressure. 


f ' 


the friction of the engine. 


V 


the velocity in feet per minute. 


33000 


the standard of horse power. 


H 


the horse power of the engine. 



RULES FOR CALCULATING. 163 

To find the area of the cylinder, square the diameter and 
multiply by .7854. 

Thus d* X 7854 = a. 
To ascertain the friction of the engine, multiply the area of 
the piston by 9.77. 

Thus a x 9.77 =/. 
Example. Required the power of an engine, of which the 
dimensions are as follows : 

Diameter of cylinder, 42 inches. 

Length of stroke, 11 feet. 

Cut-off at J of the stroke. 

Pressure on the boiler, 50 lbs. per sq. inch. 

Strokes per minute, 44. 

1st, To find the mean effective pressure. 

11 X 12=132 inches 132 -4- 4= 33 inches, length of 
cut off 132 -r- 33 = 4, the number of times to which 
the steam is expanded ; then, per table, the hyper- 
bolic logarithm of 4 is 1.386, and 1.386 -f 1 = 2.386, 
and 50 -7- 4 = 12.5. Hence 

2.386 
12.5 



11930 
28632 



29.8250 the mean effective pressure in lbs. 
per square inch on the piston. 

2d, To find the area of piston and thence the power. 

42. 2 X .7854= 1385.44 area; 1385.44 x 29.82 = 
41,313.92 the pressure on piston ; 41,313.92 X 484 
= 19,995,927.6 lbs. lifted one foot high per minute, 
which divided by 33000, gives the number of horses' 
power. 



164 RULES FOR CALCULATING. 

33000)19995927.6 (605.93 horse power. 
198000 



195927 
165000 

309276 
297000 

122760 
605.93 will therefore be the actual power of the 
engine ; but as a portion of that power is absorbed in 
moving the parts, that amount must be deducted to 
obtain the available or effective power of the engine. 
Thus 

1385.44 = the area, 

9.77 = the friction per square inch. 

969808 
969808 
1246896 



13535.7488 friction of the engine. 
41313.92 
13535.14 



27778.78 

484 velocity in feet per minute. 

11111512 
22222544 
11111272 



33000)13444639.12(407.41 effective horse power. 
132000 



244639 
231000 

136391 
132000 



43912 



RULES FOR CALCULATING. 



165 



Or, by formula. 



lst > x = Try x ( h yp- lo s- j + l ) 

Or, x = t— X (2.3026 log. y + l\ . 
J54 = a 
•f= the effective horse power. 



2nd, d 2 X .7854 = a 
V.a, 



Or, 



33000 
V. a. x 
"33000 



= H. 



/~\ 



169. When the pressure in the boiler does not exceed the 
load or weight on the safety valve, the following method has 
been long used for ascertaining what the pressure actually is. 

A tube of iron A is bent,- as represented in the diagram, 
and filled with mercury to the level a a', making a length of 14 
inches of mercury ; it is then atti ched to some accessible part 

DlAG. V. 

of the boiler by means of bolts at b b ; the 
hole c allowing a free communication be- 
tween the level of the mercury at a, and by 
means of the mercury with the atmosphere 
also ; d is a small stick of pine wood (that 
being the best material for the purpose), which 
floats on the mercury at a\ and as the mer- 
00 cury rises or falls from the pressure of the 
steam, so the upper end of the stick travels 
on the face of the index, and by its position 
points out the pressure on the boiler. Thus 
when the mercury at a is forced down one 
inch, the mercury in the other leg at a! rises one inch also, 
which together make two inches, and as two inches of mer- 
cury nearly equal 1 lb. pressure on the square inch, the steam 
is sustaining a column^ of mercury equal to two inches, or the 
pressure on the boiler is 1 lb. per square inch. 




166 



RULES FOR CALCULATING. 



This apparatus is not so convenient where steam of very 
high temperature is used, on account of the necessary length 
required ; it is, nevertheless, generally used on the boats navi- 
gating our waters. 

190. Safety Valve. — From the intimate connection which 
exists between the generating surface and the dimensions of 
the safety valve, it becomes necessary that the former should 
enter into the calculations for the dimensions of the latter ; and 
for this reason : a safety valve to be efficient should be of such 
dimensions as to allow the escape of steam to equal or rather 
exceed the generation ; otherwise steam would increase in 
the boiler and cause explosion. Such being the case, we will 
proceed to inquire into the proportion requisite to be kept be- 
tween the two. It has been found by experiment, that it 
requires about 1 .5 foot area of generating surface to convert a 
cubic foot of water into steam ; but for security, we will take 
only two-thirds of that quantity, and suppose that for every 
square foot of surface a cubic foot of water is evaporated, then 
the rule will be as follows : 

191. Divide the area of fire surface by the number corres- 
ponding to the pressure or temperature in the annexed table, 
and the quotient will be the square of the diameter of the valve 
in inches. 

TABLE XVI. 



Pressure in inches. 


Temperature. 


Density. 


Divisor. 


30 


212° 


1.00 





35 


225 


1.28 


5 


60 


250 


2.00 


15 


90 


275 


2.85 


29 


120 


293 


3.70 


45 


150 


30S 


4.70 


60 



Example. Required the area of a safety valve for a low 
pressure boiler, with 80 feet fire surface ; 5 is the divisor, as 
per table. 



RULES FOR CALCULATING. 



167 



80 

Then = 16 the square of the diameter, 

5 

and -v/16* = 4, which is the diameter. 

Or, by the following rule : 

Divide the area of the fire surface by the excess of pressure 
above the atmosphere in lbs. per square inch, and the quotient 
will be the square of the diameter. 

80 

Example. Thus — =16, and V 16 = 4 the same as above. 
5 

Having thus found the diameter of safety valve, we proceed 
to ascertain the weight to be placed upon it, and the length of 
lever. 

Rule. Find the area of the valve, and multiply by the pres- 
sure in lbs., the result will be the required weight. 

Example. The diameter is 4, and 4 2 X .7854 = 12.566 area 
12.566 X 5 = 62.830 lbs. on the valve. 

The annexed diagram represents the usual form of arranging 
the weight, lever, and valve. A is the valve, the area of which 
we suppose to be 12.566 ; B is the fulcrum of the lever E B ; 
and C is the point where the pressure is acting on the lever ; 
required the weight of the ball D to counteract or balance the 
pressure on the valve, supposing the leverage to be three to one. 



DlAG. VI. 




W77777 c 




192. Divide the pressure by the distance, and the quotient, 
minus the weight of the valve and lever, will be the weight 
required. 



168 



RULES FOR CALCULATING. 



CO QO 

Example. Thus, — — = 20.943 lbs. 

The weight of valve = 3. lbs. 
Do. of lever = 4.5 



7.5 



and, 20.94 — 7.5 = 13.44 lbs. weight of ball. 

193. For locomotive engines, and where the boiler is in con- 
stant motion, the spring balance has been attached to the lever, 
and by means of the thumb screw E, the spring can be adjusted 



DlAG. VII. 




a 



^ 




w 



to any number of lbs. on the face of the index. The rule for cal- 
culating the pressure on the valve A is, to multiply the dif- 
ference in leverage by the number of lbs. on the index, and 
with the area of the valve divide the above sum ; the quotient 
will be the pressure in lbs. per square inch. 

Example. The leverage is 4 to 1, the number of lbs. on 
the index 40, and area of valve 12.56 ; then 40 X 4 = 160-f- 
12.56 = 12.73 lbs. per inch. The exact angle for the seat of 
the valve has never yet been accurately determined ; it is usual, 
however, to make the angle less than 45°, and in many cases 



RULES FOR CALCULATING. 



169 



the seat of the valve has been made perfectly horizontal, which, 
where circumstances will permit, is probably the best. 

194. The Eccentric. — The motion of the slide, or the dis- 
tance that the valve has to travel, together with the length of 
lever, most convenient for the particular circumstances of the 
case, will determine the throw of the eccentric. The throw of 
the eccentric is the distance between B C and the distance 
travelled by the point C. 

Dug. VIII. 





is shown by the dotted circle C D. The crank shaft is repre- 
sented in section at E, and the eccentric being fixed upon it, 
the point C will, at the different positions of the eccentric be, 
consecutively in its journey round, at the points F D G. 

195. Example. The motion of the valve at H is 2 \ inches, 
and the lever I is 9J inches ; what is the requisite throw for 
the eccentric, K being twice the length of I ? K will, therefore, 
equal 19 inches, and consequently its extremity L will move 
through twice the space travelled by I, or will equal 5 inches ; 
which will be the required throw of the eccentric. 
Or, as follows, 9J : 19 : : 21 : 5. 

The dimensions of the collar B A must be made to suit the 
diameter of the crank shaft, due care being taken to give suffi- 
cient quantity of metal to the collar to prevent the possibility of 
fracture ; the throw of the eccentric must then be set off on 
the centre line from B to C, and the centre found by rule in 
art. 238. 

22 



170 



RULES FOR CALCULATING. 




Diag. IX. 



Z~-'~'" 




Again, the motion of the slide is to be 5 inches, but the 
throw of the eccentric only 2^ ; what must be the proportion of 
the levers K and I to make the arrangement complete ? 

5 

2i = — ; therefore, if K be made = 16 inches, 
2 
I will = 16 x 2 = 32 inches ; or, if I = 16, K must = 8 inches, 

The general rule will therefore be, multiply the stroke of the 
valve by the eccentric lever, and divide the product by the 
length of the valve lever ; the quotient will be the required 
throw of the eccentric. Thus, 

HxK-rI= the throw of the eccentric. 

196. Cambs. — For the purpose of using steam expansively, 
a very ingenious and simple method has obtained for setting off 
the cambs, so as to cut off at any required part of the stroke. 
The annexed diagram will illustrate the method of laying off a 
camb to cut off at one-half the stroke. 



Diagram X 




RULES FOR CALCULATING. 



171 



The circle B D C is described, and its circumference divided 
into 32 equal parts ; four of which are set off from D D' to E 
and E', and four set off to F F' ; then with the points F F' as 
centres and distance D D', the diameter of circle as radius, de- 
scribe the arcs E B and E' B, cutting one another in B ; and 
with the centre B and the same radius describe the arc FCP; 
then if the frame G G be made to touch the camb at C and B, 
it will form a half-stroke camb — for B C equalling D D', and 
the arcs F E and F' E' together equalling half the circumfer- 
ence of the circle, the slide G G will remain stationary during 
half the time of the revolution of the shaft ; that is, one quarter 
of the revolution at the top, and one quarter at the bottom. 

197. To produce a camb 
that shall cut off five-eighths of 
the stroke, divide the circle as 
before, and set off f^ or three 
divisions on each side of D D'; 
then with the radius D D' and 
centres F F describe the arcs 
E' B and E B, cutting each 
other in B ; and with centre B 
and same radius describe the 
arc F C F'; then will this camb 




cut off f of the stroke. 

198. In the same manner again, 



for 



camb : divide as 



DlAG. XII. 




before, setting off only two 
divisions on each side of D 
D', and with the same radius 
describe arcs cutting each 
other at B ; and with B as 
centre and the same radius 
describe the arc FCP. But 
as the motion which would 
be produced by the line A 
B is greater than is required^ 
a portion H B is cut off, 



•172 



• RULES FOR CALCULATING. 



Diag. xm. 



equal to the amount of its excess ; then will this camb cut 
off three-quarters of the stroke. 

199. Finally, for what is termed the whole-stroke camb, the 

circle is divided as be- 
fore, four divisions being 
setofffromDD'toEE'; 
then, with the distance 
EE'as radius and E' E 
as centre, describe the 
arcs E F and E' F', and 
with the same distance as 
an ordinate, find the curve 
F C F; then will this be a 
whole-stroke camb. 

These cambs are entirely used on the Western waters, and 
the expense of the separate cut-off valve thus obviated. 

200. The above method may be carried out to any degree 
of cut-off required, by dividing the circle into any other num- 
ber of equal parts, as into tenths or twelfths. From the cir- 
cumstance of their having originated at Pittsburgh, they still 
bear the name of Pittsburgh cambs. The name, however, of 
the very ingenious projector has been unfortunately lost. 

201. Parallel Motion. — The arrangement generally used for 

Diag. XIV. 




VI 



a i, ?r~" 



RULES FOR CALCULATING. 173 

land engines, is Bolton and Watt's original invention; and is thus 
arranged : Suppose A (diag. 14) to be the centre of abeam, of 
which B A represents one half; and suppose C to be the centre 
of a radius rod, or another beam of equal length, and B D a 
rod or link connected with the beam and radius rod at B and D, 
the point E, being the centre of link B D, will travel up and 
down in nearly a vertical line a b ; and if the piston rod of an 
engine be attached to E, it will be held in a vertical position 
during its ascent and descent. The air-pump connecting rod is 
usually attached to the beam in this manner. 

202. The following is the method of finding the length of 
the radius and parallel rods and links geometrically : With 
the centre A and distance A B (equalling half the beam) de- 
scribe the arc Bed, whose chord shall equal the length of the 
stroke ; bisect A B in e, and with A e as radius and centre A, 
describe the arc e f ; from A draw a straight line through / 
and d. Bisect the versed sine of the arc Bed, and let fall a 
perpendicular line a b, cutting A C in C, then with C as cen- 
tre and radius A e describe the arc D g h ; join the points B a, 

Diag. XV. 

B 



174 RULES FOR CALCULATING. 

cD,(iD and D C ; then B a (the front link) will equal e D 
(the back link), and a D (the parallel rods) will equal C D (the 
radius rod), and the arc D g h will equal the arc ef; and as 
the points a D are equidistant from the line A B, and the lines 
a D and D C are equal to each other, the point a in its rise 
and fall will be kept parallel to the point E, and will travel in a 
direction a b, which will be nearly vertical. 

203. Or, the following formula may be used to obtain the va- 
rious lengths : 

Let R=the radius of the beam, 

/ =the length of the parallel bars, 
and r=%he length of radius rods. 

204. Then the equation for finding the length of the radius 
Tods, will be as follows : 



R-l 2 



I -' 

Example. — Suppose the radius of a beam equals 6 feet 6 

inches, or 78 inches, and the length of the parallel bars 34 

inches, required the length of the radius rods. 

78-34=44, and44 2 

— — =56.35 inches. 

205. The most approved method of arranging the parallel mo- 
tion for marine engines, is the same in principle, though varied in 
adjustment. Let A B (diag. 16) represent half the beam ; with 
A B as radius and A centre, describe the arc Bed, whose 
chord shall be equal to the length of the stroke ; draw the lines 
BA,cA and d A, also from A as centre, and with A D as ra- 
dius describe the arc DEe. Divide the versed sine of the arc 
described by the end B of the beam, and erect a perpendicular 
b g therefrom ; and then from B c and d as centres, with the 
length of side rod as radius, cut the vertical line at g, h, and k, 
the top, middle, and bottom stroke, join the corresponding 
points g B., h c, and k d ; then from g set off on the line g b 
the centre of the pin a for the parallel rod ; in like manner, 
from the points h and k set off I and m ; then, from a I m as 
centres and distance B e, describe arcs at/n o ; also from e E 



RULES FOR CALCULATING. 
Diao. XVI. 



175 




D as centres, describe arcs cutting the former at/ no; draw 
the horizontal line n I ; with the points "f n o find the centre 
of a circle C, the circumference of which shall pass through the 
said points. Join/ C,/ a, and g B, and/ C will be the radius 
rod, fa the parallel rod, and g b the link or side rod. 

206. The simplest method of producing a perfectly vertical 
motion for the piston rod, is by means of the slides and con- 
necting rods so much in use in this country. The proportions 
between the length of stroke and length of connecting rods, or 
links, having been the result of much and careful investigation 
and experience, the following table will exhibit the usual di- 
mensions. 



176 



RULES FOR CALCULATING. 



Length of stroke, 7 feet. Length of Links, 4 feet 6 inches. 

9 " " " 6 " " 

u n u u u 7 « 6 « 

The above are the general dimensions of stroke in the 
boats on the North river. The piston rod cross-head is attached 
to the end of the beam by means of these links, and its two 
ends work on slides fixed to the cylinder and framing, so that 
the motion of the piston rod is truly vertical. 

207. The annexed diagram will show the readiest method of 
finding the centres of an ordinary boat engine. The length of the 

DlAG. XVII. *\g 







45 



<5Lq 



J 



&tf 



U 



RULES FOR CALCULATING. 



177 



stroke being decided upon, together with the length of beam and 
position of the paddle shaft as to height, we will proceed to 
explain and point out the position of the parts. 

208. The radius A B being given, and the chord a c, find 
the versed sine / B ; bisect the versed sine with the perpen- 
dicular g e, which will give the centre of the cylinder. In like 
maimer, bisect the versed sine of the chord h k, and let fall the 
perpendicular m F, which will give the centre of the paddle- 
shaft ; then from the points a, B and c as centres, with the 
length of the link as radius, cut the vertical line g e at d D and 
e, which will give the position of the piston rod cross-head at 
the top, middle and bottom stroke, from which the guides, cyl- 
inder lid, &c, must be set off. To find the length of the con- 
necting rod, place the beam horizontally, and from C measure 
carefully down to F ; then with C F as radius describe the arc 
F E, cutting the circle described by the crank pin at E, which 
will be the position of the crank, at half stroke, from which the 
position of the eccentric and cut-off camb must be decided. 

209. Piston. — Of the various plans for keeping the piston 
steam-tight in the cylinder, the arrangement of which the an- 
nexed is a diagram appears to be the most perfect. The con- 
struction is as follows : 

DlAG. XVIII. 




The piston consists of a plate A A, having a boss B cast on 
the centre, with three arms C C C also cast on it, radiating 
23 



178 RULES FOR CALCULATING. 

from the centre, and equidistant from each other ; these arms 
and the centre boss stand up from the plate A, and another 
plate D of the same thickness as A is put upon them, making 
the whole thickness of the piston ; the plate D is held in its 
place by a projection on the centre boss passing through it, and 
is fixed by screws E E countersunk into the plate D and tap- 
ped into the arms C C C. The plates A and D are turned so 
as to be just capable of moving in the cylinder, and three brass 
or cast iron (which latter material is quite as good as brass, and 
very considerably more economical) rings F F F are placed be- 
tween them ; the inner ring is equal to the width between the 
plates, and the two outer ones are each one-half the same ; one 
of the rings having a rebate or tongue projecting on one edge, 
which is carefully fitted into a corresponding groove on one 
edge of the other. The rings are turned to fit the cylinder 
very truly, and after having been hammered all round on the 
inside, are cut through in one part — the hammering giving them 
a tendency to expand, thus causing them to fly open when cut. 
When, therefore, they are put in their places in the cylinder, 
they press against the cylinder by their elasticity, and keep in 
such close contact as to make a steam-tight joint during the mo- 
tion of the piston ; the cuts in the rings being placed so as to 
cross joint. 

210. When, however, the rings become much worn, and 
they have expanded to their utmost, some other means are re- 
quisite for keeping them tight against the cylinder ; for this 
purpose, three steel springs G G G are placed in the piston, of 
the same width as the inner ring, against which they bear ; 
they are retained in their places by means of small pins with 
collars to them, one end of which is tapped into the centre boss, 
with a small nut to set it to any required position ; the other 
end pressing against the middle of the spring. When the springs 
require setting up, by unscrewing the pins a little, and setting 
up the nut, the springs are made secure. Whilst the rings 
are new, and until the elasticity is nearly gone, the springs 
are merely touching the rings ; but as the rings wear, so the 



RULES FOR CALCULATING. 179 

springs are put into operation. Access is easily obtained to the 
springs by taking off the front cover to the cylinder, and by 
means of the screws E E E, removing the plate D. There 
are many forms of metallic packings invented by different en- 
gineers, many of which are very excellent ; but they do not 
seem to combine simplicity and utility so well as to render 
them of general use. 

211. Condenser. — The capacity of the condenser ought to 
be as large as circumstances would permit, and never less than 
one-eighth the capacity of the cylinder ; and care must be 
taken in forming the passage between the condenser and air 
pump, to allow sufficient room for the injection water required 
for one stroke of the engine, besides a sufficient communica- 
tion, otherwise the connection between the air pump and con- 
denser will be stopped up by the water, as the cylinder is twice 
filled with steam for one stroke of the air pump. 

212. Air Pump. — The dimensions of the air pump are gen 
erally such as to give one-fifth the capacity of the cylinder ; 
hence, suppose the cylinder of an engine is 30 inches in diameter, 
and the stroke 7 feet, or 84 inches ; required the air pump's di- 
ameter at half the stroke. The radius of the beam is 96 inches, 
the stroke 84, and the radius of the air pump studs is 48 inches, 
then as 

96 : 84 : : 48 : 42, the length of stroke ; 

and 30 2 X48 

r ao ~— V 205.71 = 14.34 inches diameter. 

213. Cold Water Pump. — Rule. Multiply the area of the 
cylinder in feet by twice the length of the stroke, in feet, and 
that product again by 35 cubic inches, or 45 circular inches, the 
quantity sufficient for 1 cubic foot of steam, allowing for waste, 
&c., which divided by the length of stroke in inches of the 
pump, and the square root will give the diameter required. 

Then suppose A is the area of the cylinder, 
S twice the stroke also in feet, 
45 circular inches = 1 foot of steam, 
I, the stroke of the pump in inches, 
and d the diameter in inches. 



180 RULES FOR CALCULATING. 



Then /A S 45 AS45 , 

v — r~ =rf > and —— 1 =- 

Example.— What is the requisite diameter for a pump, the 
diameter of the cylinder being 2 feet 6 inches, and the stroke 
7 feet ; the stroke of the cold water pump to be 42 inches ? 



/4.9X 14x45 =8>64 incheg in diametert 
V 42 

214. Fly Wheel. — Rule. Multiply the number of revolu- 
tions per minute by the diameter of the wheel in feet, and by 
the product divide 1400 times the number of horses' power ; 
the quotient is the weight of the ring, or rim of the wheel, in 
cwts. 

Example. Required the necessary weight for the rim of a 
fly wheel of a 20 horse engine, making 24 revolutions per 
minute, the fly wheel being 18 feet diameter — 

1400X20 

— - — — =64.58 cwts. 
24X18 

215. Fly Wheel and Paddle Shafts. — It must be remem- 
b ered that where calculations of the strength and dimensions of 
shafts occur, the measurements apply only to the journals or 
bearings ; and as the different purposes to which they may be 
applied, and the different material of which they may be made, 
require different multipliers, we here subjoin the following pro- 
portions, which are the result of experience : 

216. For cast iron shafts in land engines, 450 
For wrought iron paddle shafts for sea, 356 
For wrought iron paddle shafts for rivers, 194 

General Rule. Multiply the number of horses' power by 
the multiplier corresponding to the purpose to which it is to be 
applied, divide the product by the number of revolutions per 
minute, and the cube root of the quotient is the shaft's diame- 
ter, in inches. 

Example. — Required the diameter of a wrought iron paddle 
shaft for an engine of 40 horse power, making 25 revolutions 
per minute. 



RULES FOR CALCULATING. 



181 



3V 



/356X40 



25 



= 8.28 



217. The Governor. — The governor is attached to steam 
engines and other machines for the purpose of regulating the 
supply of steam or other power to the demand, or to the re- 
sistance to be overcome. In the steam engine, this is effected 
by the action of the centrifugal force acting on two balls, or 
weights, and by its increase or diminution, elevating or depressing 
their plane of gyration ; the slightest variation in speed being in- 
stantly exhibited by a corresponding alteration in their position. 

Suppose A B to be a vertical shaft, having a collar at D, 
which is attached to the arms of the balls C C by means of 

DlAG. XIX. 




rods which move on pins at their extremities a a; hence it is 
obvious that if the shaft A B is made to revolve rapidly on its 



182 RULES FOR CALCULATING. 

axis, the balls C C will fly off in the position shown by the 
dotted lines, and by such movement will have drawn the move- 
able collar D up the shaft into the position shown by the dotted 
centres c c ; and if one arm of a lever or handle be attached to 
the collar, it will raise or depress that lever according to its ex- 
tent of motion. 

218. In adjusting the different parts of the apparatus, it will 
be necessary to consider the position of the balls corresponding 
to their mean velocity, the range of motion, and the weight and 
velocity of the balls. 

v The vertical distance between the point of suspension and the 
plane in which the centres of the balls revolve, is the same as the 
length of a pendulum which makes two vibrations in the same 
time the balls make one revolution. The usual velocity of the 
balls is 30 revolutions per minute ; therefore, the height from 
-centre of suspension to centre of balls should equal a second's 
pendulum, that is 39.14 inches. If any other number of re- 
solutions are required, divide 35,226 by the square of that 
;number. 

219. Example. — Thus, 35 revolutions are required ; what 
must be the height from the plane of revolution to the centre 
of suspension ? 

35 2 = 1225 

and = 28.756, height required. 

220. Or divide 375 by twice the number of revolutions, and 
the square of the quotient will be the height required. 

Example. — What is the required height for 42 revolutions ? 
42X2=184 

and — = 4.46 2 = 19.8916 inches. 

84 

221. Or thus, the height being known, required the num- 
ber of revolutions. 

V19.9 = 4.46 X 2 = 8.92, 

, 375 
and — - = 42 revolutions per minute. 



RULES FOR CALCULATING. 183 

222. The greatest variation should not exceed one-tenth of 
the velocity, that is, one-twentieth above and one-twentieth be- 
low the mean ; and the range of the plane of revolution will be 
nearly one-fifth of the height of suspension above the plane 
of revolution at its mean velocity. Thus, the mean height 
being 

39.14 + 3.914 = 43.054 
39.14 — 3.914 = 35.226 
The difference = 7.828 

One-fifth of 39.14 = 7.828. 

The balls vary in weight from 15 to 80 lbs. each ; and when 
at rest, should form an angle of about 30° with their axis. 

223. The method of arranging the governor, lever work and 
throttle valve, is explained in the following diagram. A B, the 
upright shaft or axis of the governor, which receives motion by 
means of a cord passing round the pulley at B, and round a 
corresponding pulley on the crank shaft of the engine or other 
convenient part. C C the balls ; D the moveable collar con- 
nected with the arms H H, by means of the rods 1 1, which 
move on pins at their extremities. E the lever, having a fork 
at one end, which rides in a groove in the collar D, and con- 
nected at the other end by the rod F to the throttle valve lever, 
shown by the dotted lines K. G is the throttle valve, which 
is shown wide open in the steam-pipe, the engine being sup- 
posed at rest. 

224. The exact length of the levers must depend on the size 
of the valve and motion of the collar D, and can be arranged in 
the same manner as the eccentric levers. 



184 



RULES FOR CALCULATING. 
Diag. XX. 




225. The dotted lines in the diagram exhibit the position of 
the balls, collar, and valve, when the engine is working at the 
maximum speed required ; for the further adjustment, however, 
requisite upon change of temperature or from other causes, 
there is usually a turn-buckle on the rod F, by turning which, 
the engine may be made to receive more or less steam, as the 
work to be performed requires greater or less velocity, or to 
compensate for other causes. To find the requisite diameter 
of the two pulleys, or the number of teeth in the wheels to 
produce any given velocity, the following rule is to be used : 

226. Rule. Multiply the diameter of the pulley, or number 
of teeth in the wheel on the governor spindle, by the velocity 
of the spindle, or number of revolutions per minute, and divide 
by the velocity or number of revolutions of the engine in the 
same time ; the quotient is the pulley's diameter, or number of 



RULES FOR CALCULATING. 185 

teeth in the wheel on the fly-wheel shaft. Or, multiply the 
velocity of the engine per minute by the diameter of the pulley, 
or number of teeth in the wheel on the fly-wheel shaft, and 
divide by the required velocity of the governor ; the quotient 
is the pulley's diameter, or number of teeth in the wheel on the 
governor spindle. 

227. Example 1 . Required the diameter of a pulley for the 
spindle of a governor, to perform 36 revolutions per minute ; 
velocity of the engine 22, and the diameter of the pulley on the 
fly-wheel shaft 18 inches. 

— — — = 11 inches diameter. 
do 

228. Example 2. Suppose the following case : — 
The engine makes 34 revolutions per minute. 
The governor, 52 revolutions per minute. 

The pulley on fly-wheel shaft, 16 inches diameter. 
The pulley on the intermediate shaft, 12 inches diameter. 
Wheel on governor spindle, 40 teeth. 
Required the number of teeth in the wheel on the interme- 
diate shaft. 

_ 52 X 40 X 12 - , 
ThllS 34X16 - 46 teeth ' 

229. Example 3. Again, suppose the engine and governor 
situated as above, required the diameter of the pulley on the 
intermediate shaft. 

— — — — = 12 inches diameter. 

52 X 40 

The weight of the balls in lbs. ought to be about 1? times 
the length of the pendulums in inches, and the levers to the 
throttle valve ought to be so adjusted that the greatest angle the 
arms form with the spindle may not exceed 45°. 

230. Piston Rods. — The diameter of the piston rods for land 
engines with long strokes, or marine engines for sea-going ves- 
sels, T \ of the cylinder's diameter ; for land engines with short 

24 



186 



RULES FOR CALCULATING, 



for locomotives ^ of the cylin- 



of 



strokes, and river engines 
der's diameter. 

231. Air-Pump Rods. — Diameter of air-pump rods, 
the pump diameter ; if of copper |. 

232. Injection Cocks. — Area of injection cock about .4 of 
an inch to each horse power ; or make the diameter of the cock 
y 1 ^ of the cylinder's diameter. 

233. Chimnies. — The diameter of steam packets and loco- 
motive chimnies equal the diameter of the cylinder ; in vessels 
with only one engine, f of the same. 

234. Water Gauge.— Many methods have been adopted for 
ascertaining the level of the water in the boiler, but all of them 
are more or less faulty ; the annexed diagram represents a 
method now generally adopted, where steam of high tempera- 
ture is used. 

DlAG. XXI. 





a 



a 



52F-. 




A A are two stop-cocks, secured to the boiler by means of 
nuts d d ; B is a glass tube cemented into the cocks A A, and 
C the level of the water in the boiler ; thus when the cocks 
are both opened, the water rises to its level in the tube, and the 
steam occupies the remainder ; any variation of level is of 
course visible. 



RULES FOR CALCULATING. 



187 



235. Another method is by gauge-cocks, of which there are 
two, and often three, attached to the boiler, which are opened 
and shut when the engineer pleases ; from the upper one steam 
is expected to blow oif, and from the lower one water ; conse- 
quently when the level of water falls below D', so that steam 
blows off, the engineer is prepared to remedy the evil ; and 
when water blows out of D, he is equally aware that no more 
water is then required. 

236. Steam Whistle. — In consequence of the various acci- 
dents which occurred, and indeed which do continually occur 
upon rail-roads, many different schemes were tried for warning 
the public from the track on the approach of a locomotive 
engine ; amongst the most effective is the steam whistle, the 
invention of an ingenious artisan of Liverpool, England. The 
following is a description of it : — 

DlAG. XXII. 





^Jp 



A A, the flange, by which it is attached to the boiler ; B r 
the passage for the steam into E, an inverted funnel with holes 
at G, to allow the steam to pass out between the cup F and 
funnel E, through the narrow opening L L, formed by the close 
proximity of the two ; the bell or cup K is fixed to the funnel 
E by means of the stem H, and the edge of the cup K is direct- 



188 RULES FOR CALCULATING. 

ly over the opening L L, at half an inch distance ; there are 
small holes left in the bell at M M to allow the steam to escape. 
The handle D is made sufficiently large, to enable the engi- 
neer to turn on just so much steam as will produce the greatest 
effect. The whistle may be heard at a very considerable dis- 
tance. 

237. Problems. — To find the versed sine, the radius and 
chord being given. 

DlAG. XXIII. 



A<~ 



Set off to a scale A B = the radius, and C D at right angles 
thereto = the chord ; then, with the distance A B and centre A, 
describe the arc a B c ; draw the lines a C and c D || to A B, 
and cutting the arc a B c at a and c, join a c ; then will b B 
be the versed sine. Or, numerically, as the diameter is to half 
the chord, so is half the chord to the versed sine, the result be- 
ing divided by two. 

238. To find the radius, the versed sine and chord being 
given. 



RULES FOR CALCULATING. 



189 



Dug. XXIV. 



.JL--* 



k:i-"'" 



A 



r 



v 



Let C D be the chord, and b a the versed sine ; required the 
radius of the circle. With the centre a, and any distance a c, 
describe the arcs at c, d, e, f, and with centres C and D and 
the same radius, describe arcs cutting the former at c, d, e,f; 
draw straight lines through the points c d and ef, and the point 
A where the lines cut each other will be the centre, and A a 
the radius of the circle, whose versed sine and chord were given. 
Or, numerically, thus : as the versed sine is to half the chord 
of the whole arc, so is half the chord of the whole arc to the 
diameter, the versed sine being added. 

239. Steam Engine Indicator, or Dynamometer. — This use- 
ful, and we mav say valuable, machine, was first suggested by 
Mr. Watt, being one among the many important inventions of 
that truly great man. It appears, however, that the machine 
was improved by Mr. Southern, who put the sliding-board and 
counter-weight to it, with tracing-point. As a proof of the 
originality of the machine with Watt, there are, at this day, 
diagrams with the board and tracing-point, as far back as 1802, 
among the archives at Soho. The machine, as improved by 
Mr. Southern, was used until an ingenious mechanic of Glas- 
gow, Mr. John Macnaught, added many valuable improve- 
ments. Our Cornish brethren have found that, without this 
instrument, it is very difficult to get the true and beneficial 



190 



RULES FOR CALCULATING. 



effects of expansive steam ; it is also used in many of the 
manufactories of that country. By it, the proprietor can ascer- 
tain, in one minute, the working condition of the engine ; he 
can detect neglect in his engineer ; can demonstrate the quan- 
tity of power required to overcome the friction of the engine, 
to give motion to the shaft and mill-gearing, or to drive the 
machinery. He can tell the power expended to drive any part 
of his works ; or, if power is let off, he can at any time prove 
what power his tenant consumes ; he can ascertain the friction 
of the machinery, when using different oils ; and can guide 
himself, with certainty, in the choice of that which is best. He 
can ascertain the expenditure of steam, when injecting water at 
different degrees of temperature ; and can compare the saving 
arising from the use of cold water, with the expense of pro- 
curing it. In fact, by this instrument, he not only can find out 
the most economical way of working his engine, but he can 
measure the expenditure, and regulate the distribution of power, 
at all times. 



Diag. XXV. 




240. The cylinder of 
the indie ator a is equal to 
\ of a square inch ; the 
dimensions on the scale 
t 1 q of an inch; each 
division representing 1 
lb. of pressure on the 
square inch of the pis- 
ton. 

When the cock e is 
shut, the index will 
stand at 0, or zero ; 
when open, the pres- 
sure of steam will be 
exhibited above 0, and 
the vacuum below. 



RULES FOR CALCULATING. 



191 



The cock e should be placed in the grease-cock, on the 
cylinder cover of the engine, or a separate opening may be 
made for it ; on opening the cock e, the small cylinder a be- 
comes part of the engine cylinder, and the small piston / is 
acted upon in the same ratio as the piston of the engine ; to the 
piston-rod g is attached the index hand d, in the end of which 
is affixed a pencil, which is acted upon by the piston /, when 
rising or falling, from the effect of either pressure or vacuum. 
The small cylinder c is covered with a sheet of paper, and at its 
upper extremity is a spring h, much about the size of a watch- 
spring ; the horizontal pulley I has a cord b, passing from its 
edge around the perpendicular pulley J. By attaching the cord 
h to the radius bar of the engine, or at any other convenient 
place where the motion is equal to the circumference of c, it 

DlAG. XXVI. .-n ri , 

will readily be perceiv- 
ed, that from the move- 
ment of the piston/ and 
the cylinder c, the pa- 
per will receive a curv- 
ed line, (as shown in the 
accompanying diagram, 
which was furnished 
me by Mr. Peterson, 
the intelligent and very 
obliging engineer of the 
Steam Ship British 
Queen, which was ta- 
ken during her voyage 
to New- York, in the 
month of May, 1840) 

, showing the average 

pressure from f , f , and 
■f, cut-off — the pressure 
in the boiler being at that 
time 6 lbs. ; the annex- 
ed being an exact fac- 
simile of the one taken. 




192 RULES FOR CALCULATING. 

241 . Supposing the paper to be fixed in the cylinder already- 
described, and the pencil ini 1 ned back, and the cord c at- 
tached to the radius rod, as before described ; the moment the 
stroke turns and the pencil point is thrown down, the line D will 
be described ; which will be the atmospheric line, or line of zero. 
Then, at the turn of the next stroke, the cock e being opened, the 
pencil point will move from D to E, which will show the ex- 
treme pressure of the steam on the piston above that of the at- 
mosphere. We will follow this line from E to F, which is the 
point of cut-off ; following the line to G, it will show where the 
pressure of the steam gets below the line of zero, and decreases 
until the piston gets.. to the lower end of the stroke H, when the 
piston will turn and the line I J will show the amount of vacu- 
um gained. 

242. The curves A, B, C, being the curves of J, f, and f, 
cut-off. 

243. To ascertain the result of each, you apply a scale of 
tenths and decimals, which will show lbs. and decimals of lbs., 
and get from each of the 10 divisions of the diagram marked a, 
b, c, d, e, /, the amount of effect produced by steam and 
vacuum ; add these up and divide by the number of divisions, 
10, and the result is the mean effective pressure throughout the 
stroke, the results are as follow : — 

Average at f cut-off, 17.62 lbs. 

Do. " | . . . . 15.93 " 

Do. " | . . . . 13.86 " 

The pressure in the boiler being 6 lbs. 

244. The following table will show the average working of 
the British Queen Steam-ship, from the time of her leaving 
Portsmouth until her arrival at New-York, in November, 
1839. 



TABLE, ETC. 

TABLE XVII. 



193 



£ 


i> c 


Expans. valve 
showing at what 
pt. of the stroke 


of va- 

. the 

side 

iches. 


c'g 


IE o 


Consumption 


Consumption 


1 


t o c5 


u o "o '7 


'J3 <d 

3 a. 


*o A 


of coals 


p. hour. 


of coals 


>er day. 


> 


. 3 


the cut-off took 


W) C ^j 


*S 2 


"2 -I 










£ 


9 ^ £ 


place. 


owe 


W 3 




Cwt. 


qrs. 


Tons. 


cwt. 


4 


4.7 


2-S cut-off. 


291 


10.4 


7.6 


23 


3 


28 


2 


A 


4.9 


2-8 " 


291 


9.5 


6.4 


25 




30 




e 


4.6 


2-8 « 


291 


11.7 


8.4 


26 




31 


4 


7 


4.9 


2-8 » 


291 


11.3 


8.4 


24 




28 


16 


8 


4.8 


2-S " 


291 


10.8 


7.6 


24 




28 


16 


9 


5.0 


2-8 " 


29J 


12.3 


9.4 


28 




33 


12 


10 


4.8 


2-8 « 


291 


12.5 


8. 


25 


2 


30 


12 


11 


4.S 


3-8 1 


• 


291 


11. 


7.2 


26 




31 


4 


12 


4.8 


2-8 


!3 


29j 


11. 


7.6 


27 




32 


8 


13 


4.9 


2-8 


< 




9. 


5.4 


19 


2 


23 


8 


14 


4.7 


2-8 


►a" 




8. 


4.4 


18 




21 


12 


15 


4.6 


2-8 


o 




8.8 


5.4 


19 




22 


16 


16 


4.8 


2-8 




291 


12. 


7.6 


27 




32 


8 


17 


4.9 


2-8, 


1-1 


291 


12. 


9. 


27 




32 


8 


18 


4.5 


4-8 10tol2 


291 


12.8 


9.2 


27 


2 


33 




19 


4.8 


4-81 
3-8 | -i 


291 


12. 


9. 


27 


2 


33 




20 


3.3 


291 


13. 


9.2 


28 




33 


12 


21 


4.6 


3-8 ys 


291 


12.5 


7.4 


27 


1 


32 


14 


22 


4.7 


3-8 | 3 


29| 


14.3 


8.4 


31 


2 


37 


16 


23 


4.8 


5-8 J 


29| 


15.01 


10.2 


33 




38 


12 


Cons 


>umption fror 


n noon until arrival 


at Ne 


w-Yor 


*, 16 






" betv 


veen London and P 


ortsmouth, 


70 








Total consumpt 


on, 


Tons 


702 





25 



PART VI. 



DESCRIPTION OF PLATES. 



DESCRIPTION OF PLATES. 



PLATE I. — Front and side elevation of Bolton and Watfs 
Twenty Horse Portable Engine. 

The side elevation shows in section the arrange- 
ment of the throttle valve, D valve, cylinder-casing, 
cylinder, piston, exhaust-pipe, condenser, air-pump, 
and hot-well ; also, the positions of the governor, feed- 
pump, eccentric, crank, and fly-wheel, the detail of 
which is exhibited in plate 2. 

The front elevation shows the space occupied by 
the engine, the valve-case, side-rods, balance-weight, 
fly-wheel, &c. 

This kind of engine is in great repute, from the 
fact that very little foundation is necessary, as the 
cistern, condenser, air-pump, &c. are all within the 
engine itself. The bottom plate of the cistern is 
bolted to the floor, for which purpose lugs are cast 
upon it, as shown in plan (plate 2) ; upon refer- 
ence to which, all difficulty in understanding the va- 
rious movements, positions, &c, will be removed. 

This is considered the most improved arrangement, 
as executed by Bolton and Watt, and is used in en- 
gines of all powers. The only difference existing is 
in the fact that engines of a larger power have stone 
cisterns instead of cast iron ; and the columns sup- 
porting the spring beams are fixed to blocks of stone, 
instead of being fixed to the sides of the cistern, as 
is shown in this instance. Probably, of all arrange- 
ments for portable engines, that is to say, condensing 
engines, this is the best and most efficient ; how- 
ever manufacturers may differ in opinion. 



198 



DESCRIPTION OF PLATES. 



PLATE II — Contains apian of the engine, and the governor 
in detail. — The plan of the engine : 
AAAA, the cast iron casing of the cistern. 
BB, the dotted line, shows the position of the cyl- 
inder. 

C, the exhaust-passage. 

D, the exhaust-pipe. 

E, the condenser. 

FF, the injection-cock and pipe. 
GG, the position of the D valve-case. 
HH, the bonnet of the foot-valve. 
J J, the channel to the air-pump. 
KK, the passage to the hot-well. 
LL, the hot-well. 

M, the passage to the hot water-pump. 
NN, the hot water-pipe. 
O, the hot water-pump. 
P, the bonnet of the valve-box. 
Q, the flange of the pipe. 
R, the cold water-pump. 

SSS, the lugs for bolting the machine to the foun- 
dation. 

TT, the cistern. 

W, the step or socket for the governor-spindle. 

The Governor, in detail : 
A A, the governor-balls. 

B, the spindle. 

C, the travelling collar ; C, a section of the same ; 
C, a plan. 

D, the socket for the arms ; D, a section ; D, a plan. 
EE, the arms. 

F, the horns or arms for supporting the balls when 
at rest ; F, a plan of the same. 

GG, the links ; G, a side view of one link. 

HH, the bearing for a spindle ; H, a plan thereof. 

Ill, section, elevation, and plan of step. 



DESCRIPTION OF PLATES. 199 

J, the shaft which receives motion from the main- 
shaft. 

KK, the bevilled wheels for transmitting motion. 
LL, the governor-lever in plan and elevation, show- 
ing the fork or crutch. 

MM, elevation and end view of the bearing of the 
shaft J. 
PLATE III. — The parallel motion complete, and in detail. 
Fig. 1 — Represents the parallel motion as laid flat down. 
Kk, the front links ; CC, the back links. 
GG the parallel bars. 
H, the piston-rod socket. 
I, the piston-rod. 
K, the pump-rod socket. 
L, the air-pump rod. 
M, the air-pump rod cross-head. 
N, the piston-rod cross-head. 
O, gudgeon of front links ; R, gudgeon of back links. 
Fig. 2 — An elevation of the parallel motion. 

B, the packing of the front link. 
Fig. 3 — B, a section of the same. 
Fig. 4 — A side view of strap of front link. 
Fig. 5 — CC, side view of back link. 
Fig. 6 — D, socket for parallel and radius-rod cross-bar. 

EF, sections of the back link packing. 
Figs. 7-8 — Side view of packing of back link, showing the 

joints, and slot for the key. 
Figs. 9-10 — Side view and elevation of piston-rod socket, 

with keys and gib. 
Fig. 11 — Section of air-pump rod socket. 
Fig. 12 — Air-pump rod cross-head. 
Fig. 13 — Piston-rod cross-head. 
Fig. 14 — Elevation of parallel rod, showing the ends, and 

manner of attaching it to he cross-bar. 
Fig. 15 —Elevation of parallel bar, showing the brasses ard 
slot, or chase, for the key for tightening the brasses. 



200 DESCRIPTION OF PLATES. 

PLATE IV. — Portable Ten Horse Steam Engine, as made by 
W. Fairbairn § Co., giving a side and sectional ele- 
vation of the engine. 

The cylinder is contained in the base or pedestal 
of the column. 

The D valve is attached to one side of the cylin- 
der, and worked by means of an eccentric and lever. 
There is a cross-stay which receives the end of the 
valve-rod, and steadies the motion. The piston-rod 
cross-head works in guides on the sides of the 
column ; and the connecting rod is attached to the 
cross-head, as in a locomotive engine, or similar to 
the engine in plate 10, 

The crank-shaft is supported by its bearing on the 
cap of the column, on which is the bevilled wheel for 
working the governor. 

The feed-pump is placed on one side of the cyl- 
inder, opposite to the governor, and is worked direct 
from the piston-rod cross-head. 

The exhaust, steam and feed-pipes, are conveyed 
under the floor. 

From the engine already explained in detail, it will 
be needless to introduce letters of reference in this 
case ; a careful examination of the plate will suffi- 
ciently explain what has not been noticed above. 

The geering at the side is intended to show the fa- 
cility of transmitting the motion from the crank-shaft. 

This arrangement has been considered very good, 
and is decidedly valuable as taking up very little 
room (no inconsiderable advantage in a crowded city), 
being easily put up, and being rather ornamental than 
otherwise. 
PLATE V. — Sixty-Jive inch Cylinder Engine, erected by 
Messrs. Maudslay, Sons and Field, Chelsea Water 
Works : London, 1837. An elevation of the engine 
pumps and air-vessels. 



DESCRIPTION OF PLATES. 201 

PLATE VI. — Longitudinal section through the centre of the 

cylinder nozzles, beam and main pump. 
PLATE VII.— Fig. 1. Side elevation of the hand-gear, 
levers and rods, with expansion tappet, &c. 
Fig. 2. Longitudinal section through the centre of one of 
the boilers, showing the steam-boxes, feed-heads, 
floats, &c. 
Fig. 3. Front elevation of the hand-gear, levers and 
rods, with expansion tappet. 
PLATE VIII.— Fig. 1. Front elevation of the boilers, show- 
ing the furnace-doors, steam-boxes, damper-pipes, 
feed-heads, &c. 
Fig. 2. Transverse section of the boilers, showing the 
steam-boxes, pipes and stop-valves, safety-valves, 
and pipes. 

Reference to Plate V. 
A, Cylinder. 

BBB, nozzles and valves. 
CC, condensing cistern. 

D, air pump. 

E, eduction pipe to condenser. 

F, expansion tappet. 

G, damper barrel for regulating the valves. 
H, main beam. 

I, sliding counterweight. 
KK, hoisting beams. 

LL, cranes for raising cylinder and pump covers. 
MM, catch pins. 
N, cold water-pump. 
00, hot water-pump and air-vessel. 
P, pump-rod. 
QQ, well. 

R, working barrel of main-pump. 
SS, clack barrels. 
T, air-vessel. 
V, main pipe, 
26 



202 DESCRIPTION OF PLATES. 

Not requiring, as yet, any machines of this de- 
scription, and, in fact, having only a very small num- 
ber of pumping engines in this country — though the 
time is fast approaching when such engines will be 
indispensable — we have taken this drawing and de- 
scription from that very valuable work, "Tredgold 
on the Steam Engine," lately edited by W. S. B. 
Woolhouse, Esq., F. R. A. S., &c, and for which 
we beg to acknowledge our indebtedness to that gen- 
tleman, trusting that we, ere long, may be enabled to 
return the like benefit. 

To return. This engine is single acting ; the diam- 
eter of cylinder is sixty-five inches, and the length of 
stroke eight feet ; the diameter of the working barrel 
of the main pump is twenty-five inches, and the 
length of the stroke also eight feet. The boilers are 
six feet wide, eight feet high, and twenty-five feet 
long. 

The operation of this engine and its appurtenances 
being nearly similar to the common hand-gear engines, 
it is scarcely necessary to advert to it but for the pur- 
pose of explaining that its action is only in one di- 
rection, namely, during the descent of the cylinder- 
piston. 

It may be explained as follows : 

The progress of blowing through being accom- 
plished, that is, opening the valves for the steam to 
pass from the boiler into the cylinder, and through the 
nozzles to the condenser, and thus expel the air, va- 
pour, and water through the blow-valves and valves 
of the condenser, the three valves in front of the cyl- 
inder, upper steam-valve, centre equilibrium-valve, 
and lower eduction-valve, shut again, and the injec- 
tion-cock opened, the steam and eduction-valves are 
opened ; the former to admit the steam into the top of 
the cylinder, and the latter to admit its egress from 



DESCRIPTION OF PLATES. 203 

the bottom of the cylinder to the condenser. The 
equilibrium-valve remaining shut, the pressure of the 
steam acting above the piston, with the vacuum under- 
neath it, is sufficient to move the piston ; and as it ap- 
proaches the end of the stroke, or bottom of the cyl- 
inder, the hand-gear tappets and catches operate- 
first, to shut the steam-valve ; secondly, the eduction- 
valve ; and lastty, when at the bottom of the stroke, 
to open the equilibrium-valve, and thus open the com- 
munication between the top and bottom of the cylin- 
der. The counterbalance at the outer or pump end 
of the beam then exerts a force sufficient to move 
the piston up again, and transfer the steam from the 
top to the bottom of the cylinder, when the lower 
tappet shuts the equilibrium-valve, and the action of 
its catch releases the catch of the steam and eduction- 
valves, thereby admitting of their opening as before, 
and being the means of making the motion of the 
valves continuous. 

The boilers are of wrought iron, upon the marine 
principle, securely stayed, and with safety-valves, 
feed-pipes, and the usual apparatus, with the addition 
of whistle-pipes, that old but effectual method of 
making known the deficiency of water in the boilers. 

The structure of this engine admits of its being 
worked to the various heights required for street sup- 
plies, the chief means of regulation being the expan- 
sion-tappet and safety-catch ; the latter acting when 
the stroke exceeds its proper limit. 

The counterweight for adjusting the engine moves 
between guide-strips inside the beam ; it is worked 
by a long screw, which (the cross handle being 
moveable) admits of the whole range of the weight 
between the catch pins when the engine is at work. 

The main pump and clack-seats are fixed in a 
substantial manner ; they are supported by four strong 



204 DESCRIPTION OF PLATES. 

iron beams, (through which very strong holding 
down bolts pass,) and they are steadied by iron 
plates fixed above and forced against the masonry. 
The supporting beams are fixed within four feet of 
the bottom of the working barrel, and the masses of 
stone above them are considerable. 

The pump-clacks are of gun metal, fitted with 
wrought iron plates leathered ; these are of large 
dimensions compared with the working barrel, and 
they are fixed in separate chambered seatings and 
held fast by distinct rods pressed down by set screws. 

Duplicates of such of the parts as are liable to de- 
rangement are kept in readiness ; powerful cranes 
and hoisting girders are fixed, and the various tools 
so arranged that the taking to pieces and repairing 
any part of the engine and pump, can be effected 
without loss of time. 

The engine is calculated to raise 2250 gallons of 
water per minute. 

The construction and execution of this splendid 
engine does ample credit to the skill and industry of 
the well known firm from whence it came. 
PLATE IX. Twenty horse high pressure Engine, made 
by Alexander Birkbeck 8f Son, Brooklyn. 

The arrangement usually followed in high pressure 
engines differs very little, if any, from that shown in 
the plate. In some instances, the valve-case stands 
inside the cylinder ; and the feed-pump is worked 
from the back link. The cut-off is also added some- 
times, but unless the purchaser has some reason for 
the alteration, the present form would be adhered to. 
The proportions are as follow : 

Diameter of cylinder, 16 inches. 

Length of stroke, . . . , . 4 feet. 

Length of beam, 13 feet 9 inches. 

Length of connecting-rod, . . 10 " 2 " 



DESCRIPTION OF PLATES. 205 

Length of links, 2 ft. inches. 

Length of radius bar, 3 " 5J " 

Height of beam from foundation plate, 10 " 11 " 
Width between plumber blocks, . . 1 " 5 J " 
Number of strokes, .... 40 

The slide is similar to that of the European en- 
gines, being the simple D valve. The governor, 
pumps and eccentric are all the same. The connect- 
ing rod is similar to those used in the river boats, and 
is undoubtedly better than the old-fashioned cast iron 
rod so long used. 
PLATE X. Horizontal engine and air-pump, used in the 
American Sugar House, N. Y., made by L. S. and 
T. W. Bartholomew. 

The form of engine most generally used is shown 
in the Plate. 

The arrangement is, as nearly as possible, the same 
as in a locomotive engine ; excepting that no revers- 
ing motion is here necessary. 

The great facility of fixing and putting together, 
as well as their cheapness, will always cause this 
kind of engine to be much used. 

This engine is used for the purpose of creating a 
vacuum, by means of the air-pump, which is laid 
down in the plan, for the purpose of crystallization. 
The stroke is 3 feet 4 inches ; the connecting rod, 9 
feet 5 J inches. The cut-off is used and worked by 
a camb on the crank-shaft ; the valve being closed by 
means of the spring, shown by the dotted lines, be- 
neath the bed timbers. The air-pump is worked by 
a crank on the end of the fly-wheel shaft. 
PLATE XL Horizontal Engine, with Sugar Mill, made by 
Levi Morris <§• Co., Philadelphia. 

This Plate shows another arrangement for a hori- 
zontal steam engine. 

In this machine, we have a bed or foundation plate 



206 



DESCRIPTION OF PLATES. 

of cast iron instead of timber, and a brick foundation. 
There is a small invert of brick in which the rock 
shaft works, the bearings of the rock shaft being se- 
cured to the under side of the bed plate ; which ar- 
rangement renders the working of the slide more 



The horizontal pipe attached to the side of the 
brick work, is for the purpose of using the exhaust 
steam in warming the water for the feed-pump ; there- 
by saving fuel. This practice has in many cases 
been attended with very beneficial effects. 

The end view shows the arrangement of the sugar 
mill, and gearing for driving the same. 

The working parts of the engine are finished with 
great care and exactness, and the whole machine is 
good and serviceable ; at the same time, the cost is 
comparatively small. 

The demand for these machines is chiefly confined 
to the West Indies, for the purpose of making sugar. 

PLATE XII. Elevation and end view of the Steam Engine 
of the U. S. Mint at Philadelphia ; arranged and 
laid down by Mr. Franklin Peale. 

The arrangement of this engine will be seen by 
inspection ; but the many novel and ingenious adapta- 
tions will require more elaborate description. The 
close attention that has been paid to the order of 
architecture selected is very obvious in the entabla- 
ture, the capitals of the columns, the ornamental tri- 
pod stand of the governor, the etruscan vase for the 
starting handle, and the fret work of the eccentric 
lever ; the mouldings on the different bosses and 
shafts ; the bonnets for the valve-cases ; all suf- 
ficiently attest the talent and application of the maker. 
The power is communicated, by means of a strap, 
to the room below, where it is distributed and again 
returned directly to the machine it has to drive ; thus 



DESCRIPTION OF PLATES. 207 

preventing that noise and dirt which so generally at- 
tend the presence of gearing in a room. 

The cord that works the governor is also conducted 
below, where the motion is transmitted to the spindle. 

The novel method of adjusting the throttle-valve 
is very ingenious and clever, and is admirably calcu- 
lated to effect the desired end. 

The index for pointing out the excess or diminu- 
tion of speed is well worthy of attention. 

PLATE XIII. Fig. 1. Apian of the entablature, showing 
the arrangement of the plumber blocks, eccentrics, 
fly wheel and dram, a a, the entablature, supported 
on the columns, as shown by the dotted circles nn; 
bbb, the three plumber blocks ; c c, the entablature 
for supporting the third or outer plumber block, and 
taking part of the strain of the main frame ; d d, the 
fly wheel shaft ; e e, the two cranks ; f, the connect- 
ing rod end ; g g, the two eccentrics, one working 
the half stroke and the other the regular stroke of 
the engine ; h, the pulley for the governor motion ; 
k, the fly wheel ; m. the drum for transmitting the 
power of the engine, by means of the strap 7. 
Fig. 1 A. The form of the crutch of the connecting rod, 
which is necessary, to enable it to pass the feed 
pump in its stroke. This is forged, together with the 
rest of the connecting rod. 
Fig. 2. A plan of the arrangement of cylinder and valve 
cases, also showing the direction of the steam pas- 
sages, a a, the entablature; b, the cylinder; c, the 
half stroke valve case ; d, the valve case ; e, the cyl- 
inder lid ; f, the gland of the stuffing box ; g, the 
piston rod ; h, the piston rod cross-head ; k, the pump 
rod ; I 1, the ends of the fork of the connecting rod ; 
m, the lid of the valve case ; m\ the lid of the half 
stroke ; n, the gland of the stuffing box for the valve 
rod ; n', the gland of the stuffing box for half stroke 



208 DESCRIPTION OF PLATES. 

valve rod ; o o, flanges cast on the valve cases, by 
which they are secured to the entablature ; p shows, 
by the dotted circle, the steam pipe ; q, the eduction 
pipe ; r, in both cases, shows the steam passage 
going from c to d ; s s, the steam passage to top of 
cylinder ; 1 1, the steam passage to bottom of cylin- 
der ; u, the cylinder bottom ; w, the half stroke valve 
case bottom ; x, the valve case bottom ; y, the valve 
rod ; y\ the half stroke valve rod ; z z, two chipping 
pieces for fitting on the standard for stopping gear. 

Fig. 3. A section of the half stroke valve-case, entabla- 
ture and steam-pipe, a a, the entablature ; c, the 
valve-case ; 6, the valve or slide ; r r, the steam pas- 
sage ; p, the steam -pipe pass'ng up cne of the col- 
umns d d; e e, the capitals ; ff, the joint by which 
they are connected to the columns ; o o, the flanges 
for fixing the valve-case to the entablature. 

Fig. 4 shows an end view of the valve-case with the bot- 
tom cover, w ; o o, the flanges ; a, the entablature ; 
e, the capital ; /, the joint. 

Fig. 5, is a section of the valve, valve-case, steam pas- 
sages, entablature, capitals, &c. a a, the entabla- 
ture ; b, the D valve ; d, the valve-case ; e e, the 
capitals of the columns ; /, the joints ; d l d\ the col- 
umns ; o o, the flanges ; q, the eduction or exhaust- 
pipe ; r r, the steam-pipe leading from the half stroke 
valve ; s s, the steam way to top of cylinder ; 1 1, the 
steam way to the bottom of cylinder ; y, the valve-rod. 

Fig. 6. A section through the valve-case and valve, show- 
ing their transverse dimensions. 

Fig. 7, is an elevation of the arrangement for throwing the 
eccentric rod out of gear. 

a, the eccentric rod ; b, the hook of the same ; d, 
the enlarged part of the valve-rod working in the 
guide, c ; e, the standard ; /, the handle or lever 
moving on the joint h, and bearing the roller g at- 
tached to it; on which, when the handle/ is raised 



DESCRIPTION OF PLATES. 209 

to a vertical position, the eccentric rod travels. b\ 
the pin on which the hook b rests, when in gear. 

Fig. 8, is a plan showing the arrangement of the parts ; 
the same letters refer to the same parts. 

Fig. 9. End view, showing the position of the tightening 
screw k. 

Fig. 10, shows the method of making the half rule joint h. 
PLATE XIV. Details of the Engine in the U. S. Mint. 

Fig. 1, is an elevation of the feed-pump, a a, the work- 
ing barrel of the pump, which also acts as a guide 
for the piston-rod ; the pump-rod being merely a con- 
tinuation of the other, b b\ the two standards of 
the pump, of which b' is the receiving and discharge 
pipe, c c cc, ornamental framing for stiffening and 
securing the work. 

Fig. 2. An end view of the pump, showing the method 
of fixing the working barrel a to the standard b, 
by means of the screws old ; the gland of the stuffing 
box being secured by means of the screw e e. 

Figs. 3, 4, and 3 A, are elevations and end view of the 
pump-valves ; the same letters referring to the same 
parts in each figure, a, the valve ; b b, the pas- 
sages ; c c, the metal forming the valve seat ; d d, a 
strap with projecting pieces inside, which by press- 
ing against e e, when the screw / is tightened, hold 
the bonnet m firmly in its place, g, a part of the 
connecting pipe which is fitted to c c with a ground 
joint and retained in its position by means of the set 
screw h, w r orking in the plate k which is connected 
to the entablature by means of bolts passing through 
the holes 1 1. 

Fig. 3 A, is a side view of the plate k, and set-screw h. 

Fig. 4. An end view of the valve-seat and bonnet, and 
one of the passages, also showing the alteration of 
form in the passages requisite for preserving an equal 
27 



210 DESCRIPTION OF PLATES. 

area of water-way, and keeping the whole arrange- 
ment as small as possible. 

Fig. 5 — shows an arrangement for a joint in the pipe ; 
a a, the main piece ; b an opening or passage running 
at right angles from the passage ; b' — c c, bolts for 
the purpose of connecting the joint e e, the main 
piece a a, and a similar joint to e e, firmly together; 
dd dd, four holes which run through a a at right an- 
gles to the bolts c c. 

Fig. 6 — Shows the face of a joint, and the manner in which 
the passage b leaves the passage b' b } ; d d, the bolts 
for connecting a to another piece, for the purpose of 
continuing the communication. 

Fig. 7 — Is an elevation of one of the fly-wheel or crank- 
shaft plumber-blocks. 

a a, the body of the plumber-block ; b, the cap ; 
cc, the two brasses ; d, the open space or bearing for 
the journal of the shaft ; e e, two strong bolts which 
connect the plumber-block to the entablature, and are 
secured by means of the nuts//, which also act as 
dowels for preventing motion in the bearing ; g g, the 
bolts for securing the cap and its brass to the body 
of the plumber-block, which are also secured by the 
nuts h h, which act as the nuts//, thus rendering any 
motion very unlikely ; n n, two keys which bear 
against the lateral faces of a chase, cut in the under- 
side of the block, on their outer sides, and against a 
packing piece o cast on the entablature, on their inner 
sides, tending to render the stability of the bearing 
still more secure ; I, is a strap or projection on the 
cap for strength and ornament. 

Fig. 8 — Is the plan of the plumber-block, showing the 
nuts k k, the top of the bolts g g, and the turned 
edges of the brasses c c. 

Fig. 9 — Shows the arrangement of the starting-valve? 
throttle and safety-valves. 



DESCRIPTION OP PLATES. 211 

a a, the two pipes which conduct the steam from 
the boilers to the main pipe b. 

c, the safety-valve ; d, the valve-case, having an 
egress-passage e to conduct the blow-off steam away ; 
/, the lever of the safety-valve ; g, the top of valve- 
spindle, which presses against the lever ; h, the ful- 
crum or centre round which the lever moves ; r, a 
small hole for elongating the lever, if necessary ; k, 
the starting-valve for shutting off the steam or letting 
it on ; I, the valve-case ; m, the stuffing-box and 
gland of the throttle-valve ; n, a pipe connecting the 
throttle-valve with the starting-valve k ; o, a bridle or 
bearing for retaining the screw p against the spindle 
of the valve k. 
PLATE XV. — Details of the Engine in the United States 

Mint. 
Fig. 1 — Is an elevation of the tripod-stand and governor. 
«, the base ; b, the upright or shaft, branching out 
near the top into the arms ccc, which support the 
hollow circular plate d ; e, the index ; f, a socket 
through which the governor-spindle passes, and in 
which it revolves ; g, a collar ; h h, the centres of the 
links k k ; 11, the upper ends of the links, where 
they are attached to the arms mm ; nn, the upper 
extremities of the arms m m, where they are attach- 
ed by means of pins to the spindle r ; o o, the gov- 
ernor balls ; p p, the arms or horns which sustain 
the balls when the machine is at rest ; q q, two 
small friction rollers fixed on the arms m m, to enable 
them to move more easily in the slots of the arms as 
they diverge or converge to the centre of motion. 
Fig. 2 — Is a ground plan of the base, showing the form of 
the tripod. 

aaa } the base ; 6, the hollow shaft or column. 

Fig. 3 — Is an enlarged plan of the under side of the cir- 
cular plate d. 



212 DESCRIPTION OF PLATES. 

r, the spindle ; s, the index plate. 

e, the hand or index. 

f, a small spiral spring to counterpoise the weight 
of the rod z, in fig. 4. 

v, a small plate fixed to the ring a, with a loop at 
each end, for the purpose of connecting the spring 
/to the weight or rod z ; ococ, the two pullies round 
which the cord passes that sustains the weight or rod 
z ; ij, a small plate which supports the pullies and 
weight. 

w, a small ring of metal which surrounds the spin- 
dle r, and to which is attached the hand or index. 
Fig. 4 — Is an elevation of fig. 3, the letters referring as 

before. 
Figs. 5, 6, and 7 — Are enlarged sections of the spindle 
and collar. 

r, the spindle. 

pp, part of the two arms for supporting the balls; 
h h, the holes for the pins which connect the rods k k 
with the arms 11; g, the collar through which the 
pin a passes, and which works in the slot a'. 

b, the collar which receives the fork of the throttle- 
valve lever. 

c c, the bevilled wheels by which the motion is 
transmitted from the fly-wheel shaft to the governor- 
spindle. 
Fig. 8 — Is a side view of Mr. Peale's new and delicate 
arrangement for adjusting the motion of the throttle- 
valve. 

a, a small rod attached to the lever/, and provided 
w T ith a screw Z, which works in c, a segment or rack, 
moving on the same spindle d as the lever k, and 
fixed to k. 

e e, two connecting rods which are attached to the 
levers k h, and transmit motion from the fork of the 
lever/ to the spindle of the throttle valve g. 



1 



DESCRIPTION OF PLATES. 213 

z, the weight or bar which rests in a small hole on 
the fork, and, by its weight, when the lever/ descends, 
descends also, and when the lever rises by its con- 
nection with the spring, (see fig. 3) it rises also, and 

* causes the index e to travel to the right or left of the 

centre of the plate s, as the speed of the engine in- 

§ creases or diminishes. 

n It will be obvious, therefore, that if the screw a is 

C turned t o the right hand or left, it will for each revo- 

lution either elevate or depress the rack c one tooth, and 
consequently alter the position of k and h ; thus en- 
abling the engineer to run his engine at what speed he 
pleases — the index e always pointing out when he 
exceeds or falls short of the mean. 

PLATE XVI. — Elevation of the Engine and Boilers of the 
Steam Packet "Neptune." 

This engine was constructed in the year 1837, for 
the purpose of taking passengers from New-York to 
Charleston, S. C, by Mr. James P. Allaire, of New- 
York. She performed her voyages with considerable 
regularity for several seasons ; but, owing to acci- 
dents which occurred to other packets, the"confidence 
of the public seemed considerably shaken, and the 
expenses of the voyage were too serious for the num- 
ber of passengers conveyed. The vessel was bought 
by the Texian Government last year, and now runs 
regularly from Galveston to New-Orleans. 

The arrangements differ little from the general ar- 
rangements of cross-head engines. 

The chief dimensions are as follow : 

Diameter of cylinder, 50 inches. 

Length of stroke, 11 feet 6 inches. 

Length of connecting-rod, . . 23 " 9 " 
Height of cross-head, at top of 

stroke from kelson, ... 42 " 5 " 



214 DESCRIPTION OF PLATES. 

Width between guides, ... 8 feet 8 inches. 
Diameter of paddle-wheel, . . 25 " " 
Number of strokes per minute, . 23 

The ordinary poppet valves, and the usual method 
of lifting them, are used in this engine. The two 
views here given will sufficiently explain her other ar- 
rangements. 
PLATE XVII. — Plan of the Engine and Boilers of the 
Steam Packet " Neptune." 

The plan shows the disposition of the various parts, 
as also the position of the boilers, which are connect- 
ed by a steam-pipe, working in a packed joint attach- 
ed to the further boiler. 
PLATE XVIII. — Engine of the Steam Packet "Charleston." 

This engine was built at Philadelphia, by Levi 
Morris & Co. 

The arrangement of the parts differs very little 
from that in the "Osceola." 

The principal dimensions are as follow : 

Diameter of cylinder, 48 inches. 

Length of stroke, 9 feet. 

Length of beam, 15 

Length of connecting-rod, 

Length of links, 7 

Height of beam, from kelson, 
Width between guides, . . . 
Liameter of paddle-wheel, 
Number of strokes per minute, . 
PLATE XIX.— Engine of the Steamboat ' 

by Mr. Adam Hull, New- York. 

This engine was arranged and made by Mr. Adam 
Hull, and has given great satisfaction. The work is 
well finished and put together. The ' Osceola ' has 
long been considered one of the fastest boats upon 
the North river, either of her own class, or of any 
other. 



15 " 


9i] 


nd 


les. 


19 " 







< 


7 " 


10 




« 


28 " 


7* 




t 


4 " 







< 


28 " 





" 


23 






Osceola 


,"«w 


m 


ade 



DESCRIPTION OF PLATES. 215 

The general arrangement of the engine will be 
seen on examining the plate, which represents an ele- 
vation and side view, showing the side-pipes, rock- 
shaft, valve-rods, spindles, injection-cock handles, and 
throttle-valve lever. The cut-off is closed by means 
of a spring attached to the rod, which is continued 
from the lever for that purpose. 

The chief dimensions are as follow : 
Diameter of cylinder, . . ... . . 31 inches. 

Length of stroke, 11 feet. 

Length of beam, 17 " 9 inches. 

Length of connecting-rod, . . 21 " 1 

Length of links, 7 " 6 

Height of beam, from kelson, . 31 " 
Width between guides, ... 3 " 65 
Diameter of paddle-wheel, . . 28 feet. 
Number of strokes per minute, 24 
PLATE XX. — Detail of balance-valves, shaft, cylinder, plum- 
ber blocks, and rock-shaft of steamboat ' Osceola.' 
Fig. 1 — Is a section of the top valves. 

AA, the steam-valves. 

A' A', the exhaust-valves. 

BB, the glands of the spindles. 

CC, the bonnets of the valve seats. 

DD, the guides or sockets of the spindles. 

EE, the valve-case. 

FF, the valve-spindles. 

G, the steam- way, or port. 

HH, the side pipes. [In this engine, the side 
pipes are connected to the valve-case by flanges.] 

C the bonnet or cover of the side pipe. 
Fig. 2 — Is a plan of fig. 1 . 

SS, the bearings of the valve or lifting-rods. 

T, the cap.Q, the steam -pipe. 

c ccc, the holes for receiving the bolts by which 
the bonnets CC are retained to the valve-case. 



216 DESCRIPTION OF PLATES. 

Fig. 3 — Is a section of the lower valves. 

II, two rings turned to fit into the sockets of the 
valve box, marked KK, and receive the side pipes, 
so as to form a space for packing aX aaa a. 

MM, two openings left in the bottom, which are 
closed up with bonnets similar to C, in fig. 1. 

L, the exhaust-passage, opening to the condenser. 
Figs. 4, 4 — Are the elevation and plan of one of the crank- 
shaft plumber-blocks. 
«, the journal. 
b b, the brasses. 

c, the plumber-block. 

d, the cap. 

e, the nuts for securing the cap. 
//, two strengthening webs. 

gg, two flanges for the purpose of securing the 
plumber-block more steadily to the frame. 

h h, lugs for the retaining bolts. 

k k k, bosses cast on the flanges for the bolt-heads 
to bear against. 

x, the oil-cup. 
Figs. 5, 5 — The main gudgeon plumber-block. The 
same letters refer to the same parts as in the pre- 
vious figure. 
Figs. 6, 6 — Are the plan and elevation of the lifting parts 
of the valve-rods. 

a a, the valve-rod. » 

b b, the lifting face. 
Figs. 7, 7 — Are the plan and elevation of the rock-shaft, 
showing the position of the wipers, and lever. 

a a, the rock-shaft. 

b b, the journals. 

c, the socket for the starting-lever. 

d, the eccentric-lever. 
e e, the wiper-frame. 

ff, the wipers or lifters. 



DESCRIPTION OF PLATES. 217 

Fig. 7 A — The end view of Figs. 7, 7. 

g, a slot cut in the eccentric-lever for adjusting the 
eccentric-pin. 
Fig. 8 — A section of the cylinder, port, and piston. 

A, the cylinder. 

B, the piston-rod. 

C, the piston. 
G, the port. 

Figs. 9, 9 — D, the cylinder bottom. 

G, the port. 
Fig. 10 — shows the dimensions of the port. 
Fig. 11 — A plan of the cylinder. 

EE, lugs cast on the cylinder to support the cross- 
head guides. 

a a, the bolt-holes for securing the cylinder-lid. 
Figs. 12, 13 — Elevation and side view of the eccentric. 
Fig. 14 — Plan of the shaft, showing the bearings and 
bosses for the paddle-wheel centre plates. 

A, the shaft. 

B, the main bearing. 

C, the middle bearing. 

DDD, the bosses for the centre plates. 

E, the outer bearing. 

F, the crank end, or n?ck. 

PLATE XXL— Detail of the Bed-Plate, Air-Pump, Con- 
denser, Foot-Valve, Cranks, Connecting- Rod, and 
Cross-Head of the Steamboat " Osceola." 
Fig. 1 — Plan of the bed-plate. 

A, the bed-plate. 

B, the bottom of the condenser. 

C, an opening to admit the air-pump. 

D, n opening to admit the foot-valve. 

FFF, chipping pieces left on, to make the joints. 
Fig. 2— Aside elevation of fig. 1. 

E, a groove cast on either side to retain the foot- 
valve. 

28 



218 DESCRIPTION OF PLATES. 

Fig. 3 — An end view of fig. 1. 
Fig. 4 — A plan of one of the cranks. 

«, the crank. 

b, the collar to receive the crank-shaft. 

c c, the webs on each side of the crank. 

dd, two lugs for the purpose of keeping the 
wrought iron strap ff apart from the crank, and to 
increase the strength thereof. 

g, the socket for the shaft. 

h, the socket for the crank-pin. 

e, the collar for the crank-pin. 
Fig. 5 — A side view of fig. 4, showing the dimensions of 
the crank and wrought iron strap. The letters refer * 
to the same in each. 
Fig. 6 — A plan of the other crank. 

This crank has no hole through the end at e. 
Fig. 7 — A side view of fig. 6. 

k k, two holes for the purpose of receiving the 
bolts which confine the crank-pin to its place. 
Fig. 8 — A section of the air-pump, bucket, delivery-valve, 
and waste and feed-pipe. 

G, the air-pump. 

H, the air-pump rod. 

K, the air-pump bucket. 

LL, the two valves. 

M, cast iron ring to retain the packing secured by 
screws to the bucket K. 

N, the delivery-valve, which also acts as the air- 
pump lid. 

0, the gland of the air-pump rod. 

P, the hot-well. 

Q, the waste-pipe. 

R, the feed-pipe. 

S, a small pipe for the purpose of drawing off the 
water. 
Fig 9 — A plan of the condenser ; C, the condenser. 



DESCRIPTION OF PLATES. 219 

TT, two large flanges for securing the condenser 
to the frame of the engine. 

L, exhaust-passage. 

U, injection-passage. 

a a a, small webs to strengthen the flanges. 

bbb, bolt holes. 

cc c, bolt holes in the side-flanges. 
Fig. 10 — Elevation of the condenser. 

d d d, bolt holes for connecting the lower valve- 
case to the condenser. 

The other letters are the same as in fig. 9. 
Fig. 11 — The piston-rod cross-head. 

a, the cross-head. 

b b, the journals for the two links. 

c c, the arms to receive the brasses for the slides. 

d d, bolt-holes. 

e e, projecting pieces on the arms for securing the 
brasses. 
Fig. 12 — Front and side views of the piston-rod socket. 

a, the hole for receiving the cross-head. 

B, the piston-rod. 

h, the piston-rod socket. 

k, the cotter which connects the piston-rod to the 
socket. 

g, the collar which embraces the cross-head. 
Fig. 13 — Elevation and plan of one of the brasses. 

f 9 the brass. 

ddd, bolt holes. 

n, a chase cut in the brass to receive the packing 
for the side of the guide. 
Fig. 14 — The foot-valve. 

E', the frame which slides down in the groove E. 
(See fig. 2.) 

/, the valve. 

m, the valve-spindle or pin. 
Fig. 15 — Front and side views of the connecting-rod. 

a a a, the connecting-rod. 



220 DESCRIPTION OF PLATES. 

b, the fork or crutch to embrace the end of the 
beam. 

c c, the brasses. 

dd f the straps. 

e e, the cotters. 
//, the gibs. 

gg, the pins for connecting the stays to the main 
part. 

h h, the stays. 

k k, the two struts fixed to the main part by Z, a 
wrought iron ring. 

o o, nuts for securing the stays. 

m and n, a key and gib for connecting the ends of 
the stays to the main part. 

c' c', the brasses for the crank-pin. 

d' the strap. 

e', the key. 

/, the gib for securing the brasses to the connecting- 
rod. 
PLATE XXII. — Elevation of the Engine of the Steamboat 
" Daniel Webster." 

This engine is similar to the engine of the steam 
packet " Neptune." 
PLATE XXIII. — Entire plan of the Engine, with the dis- 
position of its parts. 

A, the cylinder. 

B, the cross-head. 

C, the steam -passage. 

D, the exhaust-passage. 

E, the valve-seat. 
FFFF, the pillars. 

GGGG, the timbers of the main frame. 

HH, the main journals. 

IIII, the cranks. 

JJ, the valve-boxes of the pumps. 

K, the foot-valve. 



DESCRIPTION OF PLATES. 221 

L, the air-pump. 

M, the delivery-valve. 

N, the hot- well 

0, the hot water-pipe. 
PLATE XXIV. — Front Elevation and Section of Steam- 
Pipes and Valves. 

A A', the steam-valves. 

BB', the exhaust-valves. 

CC, the bonnets. 

DD', the valve-spindle guides. 

EE', the valve-chambers. 

FF', the exhaust-valve spindles. 

GG ; , the steam-valve spindles. 

H, the side-pipes. 

K, the bed-plate. 

L, the cylinder-lid . 

M, the piston. 

N, the piston-rod. 

00', the steam-ways, or ports. 

PP, the steam-valve lifters. 

P'P', the exhaust-valve lifters. 

Q, the steam-pipe. 

RR', the eduction-pipe. 
PLATE XXV. — Description of the Engine of the Steam- 
boat "North America" constructed and built by Mr. 
James Cunningham, of the Phoenix Foundry, New- 
York. 

An elevation and end view, showing the arrange 
ment and position of the different parts. The main 
dimensions are as follow : 

Diameter of cylinder, 

Length of stroke, 
Length of beam, 
Length of connecting rod, 
Length of links, 

Height of beam from kelson, 



42 inches. 


11 feet. 




17 feet 8 


inches. 


19 feet 7 inches. 


7 feet 6 


inches. 


32 feet. 





222 DESCRIPTION OF PLATES. 

Width between guides, 4 feet 5 inches. 

Number of strokes per minute, 44 single. 

Diameter of paddle wheel. 38 feet. 

Great attention has been paid to the construction 
of this engine — strength and durability have been 
attended to. The frame is made of yellow 
pine, well jointed and bolted together ; the mortices 
and tenons being well paid with white lead. The 
timber which bears the crank shaft plumber blocks, 
is firmly dowelled and bolted to the fore leg of the 
main frame, and further supported by large knees of 
oak, firmly- secured to the kelson. The plumber 
block itself being also held down by four two inch 
bolts secured with large washers and nuts under the 
kelson. To prevent any lateral motion in the frame, 
it is stayed with a strong diagonal frame, which is also 
secured to the side frames by means of cross bolts, &c. 

The arrangement of the working parts is simple 
and efficient. The handles for starting, stopping, 
and for the injection, are brought to one spot, thus 
enabling the engineer to attend instantly, when 
required. The arrangement of supporting the eccen- 
tric rod on a vibrating joint, renders the stopping and 
reversing much easier than without it ; and by using 
the balance valves instead of the ordinary poppet 
valves, a child may almost work the engine. 
PLATE XXVI.— Details of the Engine of the Steamboat 
"North Am rica" 
Figs. 1, 2, are sections of the balance valves, valve seats, 
side pipes, bonnets, glands, packing, and also show 
the dimensions and position of the ports. 

In figure 1, A A, are the valves, which are ground 
truly into their seats, for the admission of steam ; 
A' A', are also truly fitted to their seats ; these are 
for the exhaust. B B are the glands of the valve 
spindles FF, working through the bonnets CC. 



DESCRIPTION OF PLATES. 223 

BD are bonnets on the lower side of the valve box, 
with sockets to receive the lower end of the spindles 
FF, and thereby ensure a perfectly vertical motion. 
EEEE is the valve case, of cast iron. G is the 
port opening into the top of the cylinder. HH are 
the two side pipes. IIII are rings which are turned 
truly to fit the sockets of the valve box, and also to 
allow the side pipes to pass through them, thus form- 
ing a small chamber for packing, at «, a, a, a, which 
allows the side pipes sufficient liberty in expanding 
and contracting to prevent accident, b, b, b, b, are 
rings cast on the valve box, which also fit tight 
round the top of the side pipe. 

Fig. 2, shows the arrangement of the lower valves ; the 
letters corresponding to the letters in figure 1. K'K* 
are two bonnets attached to the lower side of the 
valve box for the purpose of closing up the two 
openings MM. 

Fig. 3, is a side elevation of the valve box and side pipe, 
showing the connexion of the steam pipe Q. N is 
the spindle of the cut-off valve, which works through 
a stuffing box V, and rests in a step or socket V. 
R is a bracket fitted with a brass and cap to steady 
the motion of the spindle N, as it is periodically 
acted upon by the lever X, which is connected by 
means of rods and levers to a camb on the main shaft, 
and is adjusted to suit the cut-off required. O is the 
spindle of the ordinary throttle valve, which works 
in a stuffing box W, and rests in a step or socket W\ 
The lever Y is attached to a handle, which is placed 
immediately within the reach of the engineer, and 
which he can open or shut at pleasure. 

Fig. 4, is a plan of figure 3, and the letters refer to the 
same in each figure. 

Fig. 5, is a plan of figure 2, showing the bearings of the 
valve or lifting rods SS, and the cap T for securing 



224 DESCRIPTION OF PLATES. 

the same, c, c, c, c, are the bolts which retain the 
bonnets CCin their places. 

As the peculiar advantages of the balance valves 
are not generally understood, it will be proper here 
to give a short description of them. 

The first account we receive of an attempt to 
make a balance valve similar in principle to those 
here described, is an experiment of Watt's, who 
applied a piston to the stem of the valve, fitted to a 
cylinder of the same diameter as the valve, on the 
opposite side of the passage, and the steam acting 
on the valve and piston equally, the difficulty of 
raising it was much reduced. The introduction of the 
slide valve, however, for a long time superseded its 
use ; and its present form has not been in operation 
any very great while. By referring to the plate, 
(26) it will be seen that the valves AA, on the left, 
(figure 1) are not of equal sizes in diameter, the 
upper being 111 inches, and the lower only 10<| ; 
also the corresponding valves AA, on the right, in 
figure 2, have the upper one lis, and the lower 10£. 
Again, A' A' on the right, in figure 1 , has the top one 
10£, and the under one Hi; A' A' figure 2, corres- 
ponding with them as before. 

Now suppose the dotted circle d, d, d, figure 1 , to 
be the opening of the steam pipe Q, and the valves 
marked AA, and AA to be opened ; the steam enters 
the cylinder at the upper port and what was in the 
cylinder is exhausted at the lower port, and vice versa. 
But here the peculiar and elegant adjustment is 
shown : when all is shut and there is a vacuum on 
either side, say the upper side of the piston, that 
vacuum will have a tendency to open A' A' and close 
A A on the steam side. But A 'A' on the steam side 
is opened at the same moment, so the tendency of the 
one to open, assists the tendency of the other to shut, 






DESCRIPTION OF PLATES. 225 

and as that tendency is merely the weight of the 
valve, plus the pressure on the ring, which is the 
difference between the areas of 10d and 11 1, which 
equals 17.27 square inches ; say the pressure is 
50 lbs. on the inch, the pressure on the ring will be 
86,350 lbs. ; to counteract this, we have 17.27 square 
inches, with a pressure of 14 lbs. on the inch, and 
14 X 17.27=241.78 ; the difference therefore will be 
621.72, and the weight of the valves added will 
make say 700 lbs., but when it is considered what a 
common poppet valve would require, it will indeed 
appear little. If the ordinary poppet valve were 
11 inches diameter, it would require 4,751,50 lbs- 
and the slides, such as are used in the British engines, 
weigh, without the friction of the faces being taken 
into account, 3,920 lbs.; but as the starting lever has 
a power of 6 to 1, the engineer merely exerts a 
power of 116.66 lbs. 
PLATE XXVII.— Details of the Paddle Wheel of the Steam- 
boat "North America." 
Fig. 1, shows the outside framing of the paddle-box, or 
as it is frequently termed, the wheel-house ; also an 
elevation of the paddle-wheel, shewing the arrange- 
ment of the buckets, arms, centre-plate, &c. AA 
is the main waling which rests upon the transverse 
timbers BB, which project from the side of the vessel. 
C the main upright on which the outer bearing of the 
paddle shaft E rests ; DD diagonal framing for ren- 
dering the upright C steady, and also for completing 
the truss formed by the four pieces. GG two lighter 
diagonals quartered into FF, which are morticed into 
AA, and firmly bolted together with I ; the foot of I 
is morticed into H, which acts as a tie to confine the 
pieces FF to their places, thus forming a stiff frame 
work for the planking of the wheel-house, and sup- 
porting the outer end of the shaft. 
29 



226 DESCRIPTION OF PLATES. 

KKK are the arms ; LL battens by which the floats 
are attached to the arms ; MM the float boards; N an 
inner ring of segments of wood for the purpose of 
staying the arms ; O an outer ring of iron for further 
security ; P the centre plate. 

Fig. 2, is a plan of the paddle wheel, showing the 
arrangement of the floats, which gives this kind of 
wheel the name of " split bucket," and also shewing 
the diagonal bracing QQ, for the purpose of prevent- 
ing vibration in the wheel. 

Fig. 3, is an enlarged view of one of the floats, shew- 
ing the method of fastening the same to the arm. 
KK are the arms, three inches by six inches deep, of 
red pine ; LL two battens of hard wood placed on 
the face of the float to retain it more firmly against 
the arm when the motion is reversed, about 51 inches 
wide at one end, and 4- inches at the other, and one 
inch thick ; the float-board M, is 5 feet 3 inches 
long, 2 feet 4 inches wide and li inch thick ; it is 
fixed to the arms KK, by means of straps passing 
round the arm, through the batten L and washer R, 
and held to its place by f screws and nuts, as shown 
in figs. 3 and 4 ; it is also held by two £ inch bolts 
and nuts at TT. 

Fig. 4. A side view of the method of attaching the same. 

Fig. 5, shows the method of connecting the outer ring 
to the arms ; <z, a, a, is a strap of iron, half an inch 
thick and three inches wide, which goes round the 
end of the arm K, and by being riveted tight to the 
rings 00, keeps the arm steady in its place. 

Fig. 6, is an elevation of the centre plate, showing the 
arrangement for fixing the arms. AAA is a plate 
with webs cast upon it, 1 6 in number, and at B they 
diverge to the periphery of the plate, thus forming 
16 spaces 6 inches wide, and 16 smaller ones. In 
the wider spaces, holes are drilled or cast for receiv- 



DESCRIPTION OF PLATES. 227 

ing the I bolts, which are used in fixing the arms to 
the plate. D is the hole in the centre, 14 inches di- 
ameter, by which the wheel is fixed to the shaft ; 
C is the ring, which is made 2 inches thick and Ih. 
wide, for the key chases. The plate A is one inch 
thick, as are also the webs BB. 
Fig. 7, shows the thickness of the plate and width of the 
boss or ring C. 
PLATE XXVIII. — Detail of the Engine of the Steamboat 

"North America." 
Fig. 1, is a section of the upper part of the cylinder, with 
the piston. 

a, is the piston-rod ; b, the key for attaching the 
piston to the rod ; c c c c, the piston showing the 
disposition of the metal ; d d, bosses cast on the 
piston to receive the bolts for fixing the top of the 
piston e e ; h h, holes to admit, the nuts for setting 
the above named bolts ; k k, small webs of metal cast 
on the upper plate for the purpose of strengthening 
the same ; ffff a number of small holes drilled di- 
agonally through the edges of the plate and piston to 
allow the steam to act against the segments g gg, &c, 
and, by the nature of their form press them 
against the inside of the cylinder, in the manner of a 
wedge. This kind of packing is much used, and, 
from its utility and economy, is considered very good. 
I I, the metal of the cylinder ; m, the top steam-pas- 
sage or port. 
Fig. 2 shows, by the dotted lines, the position of the 
bracket n, which is attached to the frame of the en- 
gine, as shown in the elevation (plate 25.) 
Fig. 3. Section of the cylinder bottom, condenser, steam- 
way, injection-passages, bed-plate, foot-valve, air- 
pump and bucket, delivery-valve and hot-well. 

O, the cylinder bottom, which is dished out to re- 
ceive the convex or lever side of the piston c (fig. 1 ) ; 



228 DESCRIPTION OF PLATES. 

p, the port or steam-passage ; q, the exhaust-pas- 
sage ; r r, injection-passages, of which there are 
three ; very strong flanges or brackets for securing 
the condenser are shown at s ; t, is the bed-plate on 
which the condenser rests, and which is bolted to it 
through its lower flange ; v, the air-pump, which is in- 
serted into the bed-plate, and likewise fixed to it by- 
means of bolts ; u, is the foot-valve ; w, the air-pump 
bucket ; x, the delivery-valve, which is cast hollow, 
and has its lower edges where it rests on the air- 
pump filed true, so as to fit and form a good joint ; — 
this serves a twofold purpose, namely, as the air- 
pump lid and delivery-valve. Its action is very simple 
and ingenious ; for when the air-pump bucket arrives 
at a certain height, the lid is raised, and the water 
flows out all round, thus discharging more 'effectually 
and rapidly than by the common valve, and requiring 
little or no power to discharge, merely having the 
weight of the lid to raise, y, is the hot-well, made 
of copper, and riveted to the air-pump by means of 
the vertical flange as shown in the drawing ; z, is the 
air-pump rod. 

Fig. 4, is a plan of the air-pump bucket, showing the 
manner of attaching the clacks to the bucket. 

Fig. 5, is a plan of the bed-plate, showing the dimensions 
of the passage from the condenser to the air-pump, 
and also showing the manner in which the foot-valve 
is secured to the air-pump, namely, by bolts and nuts, 
the holes for which are there laid down, a a a a, 
are four lugs cast on for the purpose of sustaining 
the pumps. 

Fig. 6, is the plan of the condenser, showing the posi- 
tion of the exhaust-passage g, and the injection-ways 
rrr; s s, the two flanges ; b , b'b ) b\ four lugs, to 
which a flat ring is attached, about two inches wide, 
and half an inch thick, over which is stretched 









DESCRIPTION OF PLATES. 229 

a wire web, to prevent any pieces of chips or other 
matter from getting into the condenser and air-pump 
from the river, and interfering with the valves, there- 
by destroying the vacuum. 
Fig. 7. A plan of the cylinder bottom 0, and showing the 
size of the port or steam-passage p; also the ar- 
rangement of the pillars cccccc, which support the 
cylinder, and through which the bolts pass to secure 
the cylinder bottom and condenser together. 
Fig. 8. A sectional plan of cylinder, showing the shape 
of the brackets n n, and their position on the cylin- 
der ; ddd, small brackets cast on the bottom of the 
cylinder, and also on the bottom of the condenser, to 
strengthen and sustain the flanges. 
Fig. 9, is the plan of the top of the cylinder. e } e' are 
the flanges or lugs on which the guides for the piston- 
rod cross-head are fixed ; m, is the port or steam- 
passage, and f f shows the width of the packing 
ring, 
PLATE XXIX — Represents an Engine and Paddle-Wheel 
of the Steamboat " Merrimac" in elevation and plan. 

The general arrangement of the engine will now 
be understood at a glance. 

The steam enters through the starting-valve, the 
han- of which is seen in plan and elevation ; thence 
to the side-pipe, and thence to the top or bottom of 
the cylinder, through the common poppet-valve ; the 
method of opening which at any required stroke is 
fully explained in page 170. By this arrangement, 
the valves act as cut-off valves at once ; the exhaust 
valves are opened by the ordinary whole stroke camb, 
which is the inner or lower one in the plan, and 
which, by means of a rock shaft and short connect- 
ing rod, transmits its motion to the two arms or 
wipers, which again alternately raise the valve levers. 

The feed and bilge pumps are worked from a vi- 



230 DESCRIPTION OF PLATES. 

brating or rock shaft, by means of a short connecting 
rod or link attached to the piston-rod cross-head and 
the end of the arm ; on the axis of which is a cross 
piece, to the ends of which the pump-rods are at- 
tached. 

The whole machine is strongly and compactly 
made, although in the most economical manner. The 
guides for the cross-head are bolted firmly to the bed 
timbers. The pine wood connecting rod is strength- 
ened by continuous plates bolted together at top and 
bottom, and the brasses are retained, as is usual, by 
gibs and keys. 

The crank is of cast iron, about If inches thick 
and 18 inches wide ; thus taking up little room and 
retaining great strength. 

The arrangement of the paddle-wheels is simple 
and effective. 

The actual dimensions of these machines are as 
follows : 

Diameter of cylinder, 17? inches. 

Length of stroke, 7 feet. 

Connecting rod, (generally 3j times 

the length of stroke,) 24J feet. 

Diameter of paddle-wheels, 17 feet 4 inches. 

Number of revolutions, from 20 to 30 

PLATE XXX. High Pressure Boat Engine, as used on 

the Mississippi. 

Tins plate shows an arrangement where one en- 
gine only is used, and where it is necessary to intro- 
duce the fly-wheel for assisting the cranks past their 
centre. 

The working parts are generally similar to the en- 
gines of the ' Merrimac,' though they are more high- 
ly finished. 

The camb shown in the elevation cuts off at f of 
the stroke ; the other camb, as before, being simply 
ioi. the exhaust, or giving the whole stroke. 



DESCRIPTION OF PLATES. 231 

The arrangement of the camb-frame and slides is 
here shown, as also the camb-rod. 

The feed-pump, bilge, &c. are like the others. 

The coughing-box acts in the same manner, though 
it is carried up with a larger pipe, which is an im- 
provement. 

The crank, however, is different ; the centre plate 
of the fly-wheel is shown with bosses cast on it be- 
tween opposite arms, to the outer one of which the 
connecting rod end is attached, by means of the crank 
pin. By having two holes for the pin, should acci- 
dent happen to one, the other could be attached in a 
short time ; thus obviating the delay consequent up- 
on breaking the crank. 

The arms ©f the fly-wheel are of wood, to avoid the 
chance of breaking when the paddle-wheels come in 
contact with floating timber, or when she runs aground. 

The dimensions of this engine are as follow : 
Diameter of cylinder, 30 inches. 
Length of stroke, 6 feet. 

Connecting rod, 19 ft. 10 inches. 

Diameter of paddle-wheel, 18 feet. 
PLATE XXXI. — High Pressure Boat Engine, as used on 
the Mississippi — Continued. 

The plan shows the disposition of the parts ; the 
cranks are connected by means of a link, as is fre- 
quently done in other marine engines. There are 
four distinct bearings for each shaft, with a coupling 
box between the two nearest, for the purpose of dis- 
connecting one wheel when any very sharp turn is to 
be made. This is effected in the ' Merrimac,' by 
stopping one engine ; and is a safeguard of the utmost 
consequence in avoiding snags, rocks and any other 
sudden and imminent danger. 

The other parts are the same as before, excepting 
that a little more expense has been incurred in ren- 
dering the finish of the work more sightly. 



232 DESCRIPTION OP PLATES. 

It would be needless to crowd this work with any 
more drawings of this kind of engine, as the two fur- 
nished are the only kind, strictly speaking, employed 
on the waters of the West ; that is, with and without 
fly-wheels. 

There is, however, another arrangement worthy of 
notice, which is, that the paddle-wheels in some 
boats are so planned as to be raised or depressed at 
pleasure, in case of getting into very shoal water. 
This is effected in various ways ; as, by wedges, 
screw-jacks, tackles, &c. 

We will now consider the boilers, used for genera- 
ting the steam, attached to these engines. The 
pressure on the boilers amounts to from 35 to 150 
lbs., and in many cases to 200 lbs., on the square 
inch. This, to unpractised ears, seems incredible ; 
yet such is undoubtedly the fact. Nay, it is highly 
probable that even this enormous pressure is exceed- 
ed without the knowledge of the engineer ; and here 
it may not be amiss to calculate the power of one of 
the engines with steam of 150 lbs. and cut-off at f of 
the stroke. 

Area of cylinder = 30 2 X 7854 = 706.36. 
Stroke 72 inches, cut-off 27 inches. 

72-27=2.66. 
Hyp. log. of 2.66+1 = 1.963. 
150 lbs. per sq. in.-v-2.66=56.76 relative expan- 
sion ; and 56. 76 X 1.963=111.43 lbs., mean pressure 
per square inch. 706.36X 111.43=78,709.69 lbs. 
pressure on piston. Now, 50 single strokes X 7 
feet, length of stroke, =350 feet, speed of piston per 
minute ; 

_ 78,709,69X350 
and Q3000 =834.7 horse power. 

But we must deduct the friction of the engine, 
with the atmospheric resistance, which, together, is 
equal to 18 lbs, per square inch. 



DESCRIPTION OP PLATES. 233 

rn 706.36X18X350 

lhen, ^"000 = 134.8 horsepower. 

And 834.7 — 134.8=699.9, effective power of engine. 
PLATE XXXII. — The boilers, as has already been remark- 
ed, are cylindrical, and vary in number and dimen- 
sions. There are, however, rarely less than three 
boilers for each engine ; and where only one engine 
is used, generally six. The average dimensions are 
from 30 to 40 inches in diameter, and from 20 to 25 
feet in length, with and without return flues inside. 

The boilers of the steamboat ' Merrimac ' are six 
in number, 34 inches diameter, 24 feet long, with a 
returning internal flue of 16 inches. The smoke is 
conveyed from the flues to two stacks by means of 
slanting pipes, three meeting on the one side and 
three on the other. The boilers are placed on a brick 
seating, which is contained in a wrought iron cradle 
rising up from the back of the fire grate gradually, 
towards the other end of the boiler, as shown by the 
side view. The plan of the boilers shows the ar- 
rangement of the steam pipes connecting the whole six 
boilers, and feeding from the connecting pipe in front. 

The end view shows the arrangement of fire doors, 
chimnies, and holes for clearing out the flues. The 
feed-pipes for the boilers come in under the end 
most remote from the fire. 

Were it not that these boilers are made of the best 
material — Pennsylvania boiler plate — many more ac- 
cidents would certainly occur, as the peculiar na- 
ture of the iron is their greatest safeguard. 
PLATE XXXIII. — High Pressure Steamboat Boilers, with 
Return Flues, as used on the Mississippi. 

Here is another arrangement : there being eight 
boilers for one cylinder. These boilers are fixed in a 
cradle, as before, and supported from the timber by 
means of iron legs. 

30 



234 DESCRIPTION OF PLATES. 

The feed-pipes and steam-pipes are similar to the 
other, as are also the flues and chimnies. The di- 
mensions are as follow, namely : 

Diameter, 33 inches. 

Length, 22 feet 8 inches. 

Size of flues, 18 inches. 

The boilers have the power of producing 398.18 
cubic feet of steam per minute, on ordinary occa- 
sions, and, when needed, could produce nearly double 
the amount. The expense of fuel in these boats is, of 
course, occasionally, very great indeed. 
PLATE XXXIV.— Boiler of the Steamboat " Independence," 
plying between New- York and Amboy, the mail route 
to Philadelphia and the South. 

This is the first boiler in which anthracite coal has 
been successfully used. It has 270 tubes, 6 feet 
long, and 2h inches in diameter. 

A, is the fire-box. 

B, the tubes. 

C, the chimney. 

D, the steam-room. 

E, the water-bridge. 

F, the grate-bars. 

G, the fire-doors. 

The proportion between the generating surface and 

fire grate is nearly 36 to 1, and between the fire 

grate and chimney 4 to 1 . 

PLATE XXXY.— The Boiler of the Steam Ferry Boat 

"Essex," plying between New-York and Jersey City. 

This is a compound boiler, having 800 tubes, 400 
being on each side of the fire-box. These tubes en- 
ter into two flues, which extend the whole length of 
the boiler, and communicate with the chimney by 
means of flues rising from their upper surfaces, and 
thence carried horizontally to the chimney. The wa- 
ter level of the boiler is about 8 inches above the top 



DESCRIPTION OF PLATES. 235 

of the upper flues. The arrows indicate the direc- 
tion of the draught. 

The proportion between the generating surface and 
fire grate is about 35 to 1, and between the fire grate 
and chimney 3 to 1. 

The novel arrangement of this boiler will be better 
understood by reference to the plate, in which 

A, is the fire-box. 

B, the tubes. 

C, the chimney. 

D, the lower flues. 

E, the upper flues. 

F, the steam-room. 

G, the steam-chest. 

H, the swan-neck, or steam-pipe. 

K, the grate-bars. 

L, the fire-door. 

Although, from the peculiar description of work 
performed by this boat, it would be hardly fair to com- 
pare the economy of her boiler, in regard to the con- 
sumption of fuel, with the boilers of those vessels 
that do not stop above three or four times in a voyage 
of 150 miles, (the " Essex " stopping, on an average, 
every twenty minutes throughout the day,) neverthe- 
less, there is no other boiler, with whatever advan- 
tages it may possess, that performs with less than 
three and a half times the quantity of coal that it does. 
PLATE XXXVI.— The Boiler of the Steamboat "North 
America" plying on the North River, between Albany 
and New- York, one of the last built and fastest boats 
on the river. 

This is of a cylindrical form, and, externally, simi- 
lar to the locomotive boiler. It has flues and return 
flues; the chimney is, consequently, over the fire- 
doors, and is carried up through the steam-chest. 

The proportion of generating surface to fire grate 



236 DESCRIPTION OF PLATES. 

is 22 to 1, and the proportion of fire grate to chim- 
ney 4 to 1 . 

A A, the main flues. 

BB, the return flues. 

C, the chimney. 

D, the steam-room. 
EE, the steam-chest. 

F, the bridge. 

G, the fire-door. 
H, the water-space. 
K, the grate. 

The blower is applied to this boiler, for the use of 
anthracite coal. 
Fig. 1, represents a half end view, and half transverse 

section. 
Fig. 2. A longitudinal section of the boiler. 
PLATE XXXVIL— The Boiler of the steamboat "New- York," 
Is arranged in a manner entirely different from any 
other, having neither a water front, back, or bottom. 
A, the flue. 

BB, the tubes, 250 in number, and 2j inches diam- 
eter. 

C, the chimney. 

D, the steam-room. 

E, the steam-chest. 

F, the bridge. 

G, the fire-door. 
H, the grate. 

This boiler, although having a very large genera- 
ting surface, does not give so great a proportion be- 
tween it and the fire grate, as would at first appear — 
the fire grate itself being very large. The propor- 
tion, however, is 24.25 to 1; but the proportion be- 
tween the fire grate and chimney is 14 to 1; the area 
of the grate being 70.5 square feet, which is consid- 
erably larger than the generality of boilers. 



DESCRIPTION OF PLATES. 237 

PLATE XXXVIIL— The Boiler of the Steamboat" Osceola." 
This plate shows a longitudinal and transverse 
section of the boiler, having a water back, bottom, and 
a water back to the fire-box. It is constructed for 
the combustion of wood, and for that purpose is one 
of the most effective yet made. 

A, the main flues. 

B, the return flues. 

C, the stack or chimney. 

D, the steam-room. 

E, the steam-chest, round the stack. 

F, the back of the fire-box. 

G, the fire-door. 
H, the water-space. 

The proportion of generating surface to fire grate 
is 25.13 to 1, and the proportion of fire grate to 
chimney 3.97 to 1. 
PLATE XXXIX. — Stephenson *s Patent Locomotive. — Side 

Elevation. 

This plate represents a side elevation of Stephen- 
son's patent locomotive engine, made in 1836, for the 
Messrs. Cubitt, contractors for constructing a part of 
the London" and Birmingham Railway, where it was 
used for about a year and a half, when it was bought 
by the Company, and used by them for carrying bal- 
last, and other similar work ; in which work it is still 
probably used. 

The engine here described, and shown in the en- 
gravings, contains the latest improvements, and is 
similar in construction to most of those used on rail- 
ways in England and on the Continent. 

Upon referring to the plate, the general disposition 
and arrangement of the parts will be seen. 

The chimney, man-hole, safety-valves, steam- 
chest, whistle, reversing-lever, with the position of 
the wheels and pedestal. The tender is attached, 
and shows the break, placed between the wheels. 



238 DESCRIPTION OF PLATES. 

This arrangement is considered very good, and, as 
has been mentioned above, is in general use. The 
exact points of difference will be seen by referring to 
the description of Dunham's locomotive, (page 240) 
with the drawings. (Plates 44, &c.) 
PLATE XL. — Longitudinal Section of Stephenson's Loco- 
motive Engine. 

This plate shows a longitudinal section through the 
boiler and cylinder, and likewise through the tender ; 
the section below the boiler being taken through the 
right hand cylinder and crank. 

AA, the boiler. 

BB, the fire-box external. 

C, the internal fire-box. 

D, the grate-bars. 

E, the tubes. 

F, the smoke-box. 

G, the chimney. 

H, one of the cylinders. 
I, the damper. 
K, the feed-pump. 
L, water-guage. 
M, guage-cocks. 
N, the lever safety-valve. 
O, the safety-valve. 
P, the man-hole. 
Q, the pedestal. 
R, the blow-off cocks. 
S, the steam-pipe. 
T, the steam-chest. 
U, the valve-box. 
V, the slide. 
W, the cylinder bottom. 
X, the piston. 
Y, the piston-rod. 
• Z, the cross-head. 



DESCRIPTION OP PLATES. 239 

A', the guides. 
B', the connecting-rod. 
C, the cranked-axle. 
D', the driving-wheels. 
E', the eccentrics. 
F', reversing eccentrics. 
G', feed-pump cross-head. 
K', the feed pipe. 
L', fr >nt wheels. 
M', hind wheels. 
N'N', side frames. 
O', front frame. 
P', hind frame. 
Q', the pedes'a 1 s. 
R', the bearings of the axles. 
S', the springs for driving-wheels. 
T', buffers. 
IP, ths platfrrm. 
V, the engine-pin. 
W the ccup ang. 
X', the tender-pin. 
Y', wrought iron frame. 
Z', steam whistle. 
PLATE XLI. — Plan of Stephenson's Patent Locomotive, 
with Tender, and detail of reversing gear. 
PLATE XLII. — End view of Stephenson's Patent Locomo- 
tive Engine. 
The letters refer to the same parts in each plate. 
PLATE XLIII. — Locomotive Engine, by H. R. Dunham. 

Front and side elevation of the engine, showing the 
arrangement of the boiler, cylinder, connecting-rod, 
wheels, feed-pump, guides, safety-valve, throttle- 
valve handle, and chimney. 

This engine has drawn a load up an incline that was 
equivalent to 220 tons, gross weight, upon a level, 
(including engine and tender,) at a velocity of 14 miles 



240 DESCRIPTION OP PLATES. 

per hour, with the steam at the usual pressure of 50 
lbs. in the boiler. The force required to perform this, 
moving at that velocity, is about 2050 lbs., which is 
equal to 77 horse power. 
PLATE XLIV.— Fig. 1. Plan of the engine, showing the 
position of the parts of the engine. The cylinders 
are placed on each side of the smoke-box, with an 
inclination downwards to the centre of the crank- 
shaft, which is placed behind the boiler. The ec- 
centrics, with their reverse motion gear, are placed 
under the engineer's platform, so as to be accessible 
at all times. „ The sockets for the starting-levers, and 
the safety-valves, are each exhibited in place. 
Fig. 2. An elevation of the eccentrics and reverse motion 
gearing. 

AA, the eccentrics. 

B, cranked axle. 

CC, the eccentric-rod frame. 

D, the rock-shaft. 

E, the valve-rod lever. 

F, the valve-rod. 

G, the arm of the reverse motion lever. 
H, the reverse motion lever. 

K, connecting-link. LL, eccentric-levers. 

Fig. 3. Elevation "of the rock-shaft, showing the valve- 
rod pins, bearings, eccentric-rod pins, socket-joint, 
and starting-lever sockets. 

Figs. 4 and 5. Elevation of one of the wheels, showing 
the mode of connecting the crank to the nave of the 
wheel, by letting it into a recess cast in the wheel 
for that purpose, and further strengthened by shrink- 
ing wrought iron straps around the nave. This 
method has been much praised, for the following rea- 
sons : it leaves more room between the cylinders, 
strengthens most materially the cranked axle, and is 
much less liable to accident than the old method. 



DESCRIPTION OF PLATES. 241 

Figs. 7 and 8. Elevation and plan of one of the eccentrics, 
showing the method of fixing the same into the axle. 
PLATE XLV. — Detail of Steam Cylinder, with Pump, 
Piston, Connecting-Rod, fyc. 

Fig. 1. Section through smoke-box, showing the steam- 
pipe, exhaust-pipe, cylinder-cap, valve-box, and feed- 
pipe. 

Fig. 2. Section of cylinder, steam-ways, slide, valve-box, 
oil-cup, and steam-pipe ; also, a section of the feed- 
pump, showing the retaining and delivery-valves ; by 
having two of which, the trouble occasioned by the 
hot water getting into the pump is obviated, and a 
certain effect from the pump secured. The piston, 
piston-rod, slides, and guides, with the cross-head 
and connecting-rod attached, are also shown. 

Fig. 3. Front and side views of the connecting-rod ends, 
showing the brasses, straps, keys, and gibs. 

Fig. 4. Plan of the piston, with the bottom plate removed. 

Fig 5. Elevation of the piston, showing the joint in the 

metal packing ring. 
Fig. 6. Section of the piston, showing the bosses for re- 
ceiving the bolts which secure the bottom plates to 
the piston, and also the connecting-rod. 

For a full description of this kind of piston, see 
the former part of this work. (Page 177.) 
PLATE XLVI. — Sections of the Boiler, with detail of Pe- 
destal, Throttle- Valve, fyc. 

Fig. 1. Transverse section of fire-box, showing the ar- 
rangement and number of the tubes, the dimensions 
of the steam-chest, situation of steam-pipe, and level 
of the water in the boiler. 

Fig. 2. Longitudinal section of the boiler, fire-box, smoke- 
box, and lower part of the chimney. The throttle- 
valve is shown in its place, with its standard and 
valve-rod, and the connecting-pipe to the smoke- 
31 



242 DESCRIPTION OF PLATES. 

box. The flange for receiving the connecting-pipe to 
the valve-box is also seen. 

Fig. 3, is a plan of the throttle-valve, showing the dimen- 
sions of the steam-passages, and also the slot which 
limits the motion of the valve, and through which the 
pin passes, connecting the rod to the slide. 

Fig. 4. A section of the slide, when the passage is full 
open, showing how the rod is connected to it by- 
means of the bolt or pin. 

Fig. 5, is an elevation of one of the pedestals, with the 
bearing of the axle, and the steel pin which transmits 
the pressure on the axle to the spring. 

Fig. 6. An end view of the same, showing the bolts and 
nuts which secure the pedestal to the frame. 

Fig. 7. Apian of the bearing, showing the position of the 
oil-holes, bolt-holes for securing the cap, the chase for 
the pedestal, and a section of the steel pin. 

Fig. 8. A view of the under side of the same, with the 
mortices for receiving and securing the cap. 

Fig. 9. An elevation of the bearing, showing the cap in 
place, and secured by the nuts. 

Fig. 10. A plan of the cap, showing the space for receiv- 
ing the waste oil. 
PLATE XL VII. — Elevation of Locomotive Engine and 
Tender, arranged by P. R. Hodge. 
This engine is unquestionably one of the simplest 
in construction of any yet manufactured. The 
greatest care has been taken to reduce the number 
of working parts and to render the operation of 
starting, reversing and stopping, as easy and quick 
as possible. Thus, there are two eccentrics on each 
side, which for further convenience are placed out- 
side the frame, enabling the engineer at all times to 
see that each part is in working order ; or in case of 
accident, immediately to remedy the same. The 
operation of reversing is performed by drawing back 



DESCRIPTION OF PLATES. 243 

the reversing handle, thus raising one friction roller 
and lifting one eccentric rod and lowering the other 
roller, causing the hook of the eccentric rod to receive 
the pin of the lever ; the two corresponding levers 
are connected together by means of a tumbling shaft 
passing under the boiler. There are two engines on 
the New-Brunswick and Jersey City road of this con- 
struction, and their regular performance is highly sat- 
isfactory. The original plan of this construction was 
laid down by myself, in the year 1836, for Messrs. 
Rodgers, Ketchum & Grosvenor, the manufacturers, 
at Paterson, N. J. 
PLATE XLVIII. — Elevation of Locomotive Engine and 
Tender, by W. Noi-ris, Philadelphia. 
In another part of this work, mention has been 
made of the performance of Mr. Norris's engines, — 
upon reference to the plate, it will become obvious 
by what means the extraordinary performance of these 
machines is effected. The truck frame is placed as 
far forward as possible ; the boiler is long, thus 
affording room for a connecting rod of proper length ; 
the axle of the driving wheels is placed in front of 
the fire box, thus bearing nearly -4 of the whole 
weight of the engine ; the wheels are small in diam- 
eter, and the length of stroke is increased ; thus all 
the elements, forming a powerful machine, have been 
very judiciously brought together, and the result is 
truly astonishing ; the introduction of these engines 
having nearly put aside the objections formerly so 
strongly urged against inclined planes, on account of 
the increased expenses attending the working of a 
stationary engine. The following is a summary of 
the performance of these machines : weight of 
engine 8 tons, cylinder 10^ inches diameter, stroke 
18 inches. Weight which this locomotive can draw 
up the several grades specified on the next page, and 
on a level, at the speed of 15 miles per hour. 



244 





TABLE, ETC. 










TABLE. 








369 feet 


rise 


per mile, 


tt 


16 tons 


150 " 


u 


a tt 


tt 


43 


tt 


100 " 


a 


a tt 


a 


52 


tt 


90 " 


tt 


tt a 


a 


56 


a 


80 " 


" 


a tt 


a 


63 


a 


70 " 


ti 


a tt 


tt 


69 


a 


60 " 


tt 


tt tt 


a 


78 


it 


50 " 


" 


a ti 


a 


90 


a 


40 " 


a 


a a 


a 


104 


it 


30 " 


" 


it tt 


a 


126 


a 


20 " 


" 


a a 


a 


158 


tt 


10 " 


tt 


a it 


a 


213 


a 


Level, 


a 


it a 


a 


309 


a 






INDEX TO THE PLATES. 



PAGE 

PLATE I. — Front and side elevation of Boulton and 

Watts' twenty horse portable Engine, . . . 197 

PLATE II. — Plan of the Engine and Governor in 

detail, 198 

PLATE III. — Parallel motion complete and in detail, 199 

PLATE IV. — Portable ten horse power steam Engine, 

as made by W. Fairbairn & Co., . . . . 200 

PLATE V. — Sixty-five inch cylinder Engine, erected 
by Messrs. Maudslay, Sons & Field, at Chel- 
sea Water Works, 200 

PLATE VI. — Longitudinal section through the cen- 
tre of cylinder, nozzles, beam, and main pump, 201 

PLATE VII.— Elevations and sections of parts, &c. . 201 

PLATE VIII. — Elevations and sections of boilers, &c. 201 

PLATE IX. — Elevation and end view of twenty horse 
high pressure Engine, made by A. Birkbeck 
and Son, Brooklyn, 204 

PLATE X. — Horizontal Engine and air-pump, by W. 

Bartholomew, of New-York, 205 

PLATE XL— Horizontal Engine and Sugar Mill, by 

Levi Morris & Co., Philadelphia, .... 205 



246 INDEX TO THE PLATES. 

PAGE 

PLATE XII. — Elevation and end view of the Steam 
Engine in the U. S. Mint, at Philadelphia, by 
Mr. Franklin Peale, 206 

PLATE XIII.— Details of parts of the above, ... 207 

PLATE XIV.— Details of parts, continued, .... 209 

PLATE XV.— Details of parts, continued, .... 211 

PLATE XVI.— Elevation of the Engine and Boilers 

of the Steam Packet 'Neptune,' .... 213 

PLATE XVII.— Plan of the Engine and Boilers of the 

Steam Packet ' Neptune,' 214 

PLATE XVIIL— Elevation of the Engine of Steam 

Packet ' Charleston,' by Levi Morris, . . . 214 

PLATE XIX. — Elevation and end view of the Engine 
of the Steamboat ' Osceola,' by Adam Hall, 
New-York, 214 

PLATE XX. — Detail of balance valves, shaft, cylin- 
der, plumber-blocks, and rock-shaft, . . . 215 

PLATE XXI. — Detail of bed-plate, air-pump, con- 
denser, foot-valve, cranks, connecting-rod and 
cross-head, 217 

PLATE XXII.— Elevation of the Engine of Steam- 
boat ' Daniel Webster,' 220 

PLATE XXIII.— Entire plan of the Engine of the 

Steamboat i Daniel Webster,' 220 

PLATE XXIV. — Front elevation and section of steam- 
pipes and valves, 221 

PLATE XXV.— Elevation and end view of the En- 



INDEX TO THE PLATES. 247 

PAGE 

gine of the Steamboat 'North America,' by- 
Mr. James Cunningham, N. Y., .... 221 

PLATE XXVI.— Details of the Engine of the Steam- 
boat ' North America,' 222 

PLATE XXVII.— Details of the paddle-wheel of the 

Steamboat ' North America,' 225 

PLATE XXVIII .—Further details of the Engine of 

the Steamboat 'North America,' .... 227 

PLATE XXIX. Elevation and plan of one of the En- 
gines of the Steamboat ' Merrimac,' by Robin- 
son and Minis, Pittsburg, 229 

PLATE XXX. Elevation of high pressure boat En- 
gine, as used on the Mississippi, . . . . 230 

PLATE XXXI. — Plan of high pressure boat Engine, 

as used on the Mississippi, 231 

PLATE XXXII.— Plan and elevation of the boilers 

of the Steamboat ' Merrimac,' 233 

PLATE XXXIII.— Plan and elevation of boilers with 

return flues, as used on the Mississippi, . . 233 

PLATE XXXIV.— Sections of the boiler of Steam- 
boat ' Independence,' by Dunham, N. Y., . . 234 

PLATE XXXV.— Section and plan of the boiler of the 

Steam ferry-boat ' Essex,' by Dunham, . . 234 

PLATE XXXVI.— Sections of one of the boilers of 
the Steamboat ' North America,' by Cunning- 
ham, New-York, 235 

PLATE XXXVII.— Sections of the boiler of the 

Steamboat ' New- York,' by Dunham, . . 236 



248 INDEX TO THE PLATES. 

PAGE 

PLATE XXXVIIL— Sections of the boiler of the 

Steamboat ' Osceola,' by Adam Hall, . . . 237 

PLATE XXXIX. — Elevation of Stephenson's patent 

locomotive, with tender, 237 

PLATE XL. — Sectional elevation of Stephenson's pa- 
tent locomotive, with tender, 238 

PLATE XLI. — Plan of Stephenson's patent locomotive, 

with tender, and detail of reversing gear, . 239 

PLATE XLII. — End Views of Stephenson's locomotive, 239 

PLATE XLIIL— Elevation and side view of Dun- 
ham's locomotive Engine, 240 

PLATE XLIV.— Plan of Dunham's Engine, with de- 
tails of reversing motion, driving wheels, &c. 240 

PLATE XLV. — Details of cylinder, feed-pump, &c., 

of Dunham's Engine, 241 

PLATE XLVI. — Longitudinal section of boiler, with 
details of pedestal, throttle-valve, &c, of 
Dunham's Engine, 241 

PLATE XLVII. — Elevation of locomotive Engine and 
tender, arranged by P. R. Hodge, and manu- 
factured by Rodgers, Ketchum and Gros- 
venor, 242 

PLATE XLVIIL— Elevation of locomotive Engine 
and tender, arranged by Mr. Sanno, and man- 
ufactured by Mr. Norris, of Philadelphia, . 243 



ERRATA ET CORRIGENDA. 



Page 65, Line 5 — For ingenuous, read ingenious. 
— 77 — 

A, Tubular boiler, with return flue. 

B, The cylinder. 

C, The beam, supported at the smaller extremity on a rocking 
centre, and steadied by means of the radius-rods, one of which is 
shown attached to the upright, behind the cylinder. 

D, The fly-wheel. 

E, The reservoir, for the supply of the boiler. 

F, The feed-pump. 

G, The valve of the feed-pipe. 
H, The grate-bars. 

I, The stack or chimney. 

1, The connecting-rod. 

2, The fly-wheel shaft, with the geering. 

3, The valve. 

4, The exhaust-pipe, which conveys the steam from the cylinder 
into the reservoir E, where it is used for heating the water for the 
supply of the boiler, thereby causing a saving in fuel. 

5, The feed-pipe. 

6, The feed-pipe, showing where it enters the boiler. 

7, The stop-valve of the feed-pump. 

8, The starting and stopping valve. 

9, The pump for supplying the reservoir. 

Page 126, Art. 111. — For " insufficiency of the engines," read inefficiency 
of the engineers. 

Page 145. — The credit of being the inventor of the reversing-face is due to 
Mr. Eastwick, the very intelligent partner of Mr. Harrison. These 
enterprising gentlemen have lately made very great improvements 
in Locomotive Engines. 

Page 149, Art. 174 — For " a = the diameter," &c. read d. 

Page 172. — The reader will be kind enough to transpose Diag. XIV., in- 
verted through the carelessness of the printer. 

[over. 

32 






d 

rH 



2 



H 

> 

H 
O 

O 
O 

o 

1-3 

fa 
o 



o 



fa 
o 

w 
►H- 

pa 
«! 



5 ^ 


c co co o o co co 

£ rt< ^H iO lO ^ TH 


Weight 

of 
Driving 
Wheels. 


. 1> 00 <M 

j§ CO 00 r-J^ 
►h" HO rW\ 
i— 1 >— 1 r-l'* 


•sow 


£ CM l-l l-H 
|j, CO rH rH r-( 
« OS U0 OD OS 

ot OS CO 

o O OS t- 00 OS OS 


.2 02 » 


•g CO CO 03 CO iO CO 
C rH i— 1 rH i— 1 i— 1 rH 


fla! 


CM Tt* O 

8 N ^ H 1> ^ i> 
fe CM CM i-l CO 


3*ifij 


. iO 00 o 
o CM OCtFiO 
fa if* CD CO* CO* J> CO 


2 o 6 
fa 


CD lO 

3 iO O CD* tt" OS (M 

fa CO "* CO CO CO CO 




O 00 OS 
00 CO oq 
a* CD tH CO* 1>" iO 00 
J° 00 O (M O CO CO 
« CO CO CM CO "# CM 


S3 m 

5 * 


g 10 o 

C rH rH rH i-l rH (M 


1*1 

Eh 


(M ^ OS 1- rH CO 
CO <M i> O rH CD 
rH i— 1 rH iH 


£ s* 

PS 


« rH CO CO CO O CM 

£ CO CD CO CD 00 CO 


Q pa 


J} 00 00 CO CO i> OS 

o CO CO CO CO CO CO 


S°2 

J 02 


a 00 CO CD CO 00 CO 
g rH rH rH i— 1 rH rH 




g H» Hpj 
J5 rH O rH rH rH O 




bo ?h « 55 ^ 

CO o3 © c3 « £ 



■^ 



INDEX. 



Achard, 

Adhesion on rails, . 

Air-pump, Smeaton's, . . 
Watt's first, . 
Murray's patent for 
Rules for 
Rods, rules for 

Albany, Steamboat to 

Alcoholic vapour, . . 
Cartwright's idea, 

Allaire's, Mr. J. P., engines, . 
Engine of the Neptune, 

Amonton's Fire-wheel, . 

Anderson's, Professor, employment 
of James Watt, 

Anthracite coal, 

Comparative value of, 

Archimides' Screw, Propeller, 

Architecture Hydraulique, Proney's 
Treatise on the Steam Engine, 

Atmospheric Engine, Papin's, 
Smeato>i's Portable, 
Pressure, application of 
Pressure, amount of 

Axis of beam, position of 

Backwater, methods of avoiding 
Stevens' method, . 

Bacon's opinion of the nature of heat. 

Balance Weights, objection to 

Baldwin's, Mr. M. W., first Loco- 
motive, .... 

Bank's, Mr. John, investigations of 

Banks, Sir Joseph, . 

Baptista Porta, 

Barometer, 

Baron Dupin, . . 

Bartholomew's Engine, . 

Beighton's, Henry, calculations, 

Belidor's Historical Sketch, 

Bettancouit's experiments, 

Birkbeck's, Alex., engine of 

Bituminous Coal, value of. 

Black's, Dr., Theory of Heat 

Blake, calculations of, 

Blakely, floating piston o£ 

Blast-pipe, position of, 

Blowers, dimensions of, . 

Blowing Apparatus, 

Boat, steam, flues, . 



Page. 

61 Boiler, form and dimensions of, 

134 Furnace of, . 

46 Twenty horse, 

51 Depth of water in, 

Flues and heating surface, 

179 Tubular, 

186 Evaporative power of 

109 Locomotive, 
61 Steamboat, 
65 Western steamboat,. 

110 Dimensions of, 
213 Of steamboat Independence, 

26 Ferry boat Essex, 

North America, 

New-York, . 

Osceola, 
Bolton, in partnership with Watt, 
Bcoth, Mr., boiler of, 
Boring of cylinder, Murdock's^ 
Bossut, speculations of, . 
Braithwait.e and Erricson, 
Bramah, Joseph, four way cock, 
Brancas, Giovanni, engine of, 
Brindley, James, boiler of, 
British Queen, paddle wheel, 

Performance of, 
Bucket-split, account of, 
Calculation of steam power, 
Calcutta, steam ship to, date of, 
Cambs, rules for laying down. 
Cardan, his ideas of steam, 
Car on Iron-works, 
Cartwright, Edward, engine of, 
Cawley, John, 
Chase-waler Engine, 
Charleston, steam packet to, 
Chimneys, size of, . 

Locomotive, size of, 
Chain and drum piopeller, 
Cistern injection, position of, 
Circular motion, first produced] 
Coal, bituminous, 

Anthracite 
Cock, injection, 

Rule for, 

Steam, . 
Cold water pump, rules foi 
Columbia inclined plane. 
Combustion, account ofj 



62 
25 
43 
27 
85 
41 
128 
129 
42 
57 

136 
63 
45 
15 
8 
59 

205 
31 
33 
62 

204 



47 
141 
97 



Pago. 

100 

102 

101 

102 

102 

103 

104 

104 

104 

105 

233 

234 

234 

235 

236 

237 

55 

140 

69 

70 

136 

71 

17 

41 

130 

193 

129 

31 

111 

170 

14 

53 

64 

27 

44 

110 

186 

140 

128 

29 

33 

97 

97 

29 

186 

27 

179 

138 

95 



252 



Condensation, first applied, 
Condenser, Watt's first, 
Specification, 
Guage, . . 

Capacity of, . 
Connecting-rod, 
Cornwall, engineers of, . 
Cosmo de Medicis, inventor 

steam engine, 
Coughing box, use of, 
Crawford, Dr., inquiries of, 
Crank, Watt's oiiginal claim to, 
Cross-head, Fulton's first, 
Cross-head engine, description of, 
Cunningham's engine, 
Cut-off, first application of, 
Cutting off steam, useful appli 

tion of, 
Cylinders, proportions of, 
Wooden, 

Outside locomotive, 
Locomotive, . 
Dalton, John, investigations of, 
Damper, self-acting, 
Daniel Webster, engine of, 
De Caus, Solomon, engine of, 
De Moura, engine of, 
Density of steam, . 
Denys, Papin, Dr. . 
Desaguliers, writings of, 
Dodd, Wm. G., 
Dundas, Lord, experiments, 
Dunham, engine of, 
Dupin, Baron, 

Dynamometer, explanative of, 
Eccentric, rule for, 
Eduction pipe, 
Elastic Fluids, expansion of, 

Force of steam, 
Emerson, Wiliiam, 
Engine, atmospheric, 
Self-acting, . 

Do. . . 

Double-acting, 

Do 
Rotary, . . 64, 

Expansive, . 
Compound, . 
Semi- rotative, 
Portable, 

Do 
English locomotive., 
Rules for calculating powi 
Enterprise steamship, 
Essex, boiler of, . 
Evans, Oliver, 
Evaporaiive power of boiler. 
Exhaust, lead of, 
Expansive force of stoam, 
Expansive steam, 
Fans, dimensions of, 
Fairhairn's engine, . 
Fenwick, Thomas, . 
Ferguson, lectures of, 
Field, Joshua, 
Fire Water-work, . 
Wheel, 



Page.i 

24 Fire boxes, . • 
51 Fitzgerald, Keane, . 
54 Flats, 
59 Flues, 
179 Fly-wheel, 
141 Shaft, . 

1 1 1 Foundry, West Point, 
Four-way cock, 
Formulae for locomotives, 
Friction on rails, 

Of engine, . 
Fuel, Smeaton's remarks 
Varieties of, . 
Saving of, 
Consumption of, 
Work performed by, 
Fulton, success of, . 
Furnace, internal, . 

Smoke consuming, 
Robertson's, . 
Rules for, 
Garey, Blasco De, 
Guage cock, . 

Description of, 
Condenser, . 
Steam, . 
Generation of steam, 
Gensanne, engine of 
Giovanni Brancas, . 
Governor, 

Great Western paddle-wheels. 
Grate bars, . 
Guide rods, 

Hull, Dr., plan of evaporating. 
Hall, Adam, . . 
Hand gear, 
Hard wood, 

Harrison and Eastwick, 
Hart, Dr., 

Heat, latent, . . 
Specific, . 

Effects of, . 
Waste of, 
Heating vessel, 
Surface, 
Hero, 

Hesse, Charles, Landgrave 
High pressure engine, 

Watt's patent for, 
Trevithick and Vivian 
197, 20C Birkbeck's, . 

137 Hodge, P. R., . 
161 Holmbush Mines engine, 
111 Holyhead and Dublin packet! 
1<)5 Horizontal engine, . 

75Hornblower, engine of, 
104 Howard, ideas of, 
144 Hulls, Jonathan, 
8, 59 Humphrey, Potter, . 
, 118 Hyperbolic Logarithms, 
96 Inclined plane, 
200 Indicator, 
71 Injection cock, 
47 Cistern, 

13(' Jouffray, Marquis De, 
19 Kier, Mr., engine of, 
26 Kircher, Father, engine of, 



125 

43 
58 
110 
213 
221 
57 

111, 113 

38 
49 

136 

141 
72 
68 

110 
16 
37 
35 
25 
32 

111 
72 
139, 239 
59 
113, 189 

169 
29 
84 
88 
41 
26 
37 
38 
52 
57 
118 
58 
58 
59 
68 



66, 



Page. 

140 

40 

124 

102, 105 

41 

180 

111 

. 26, 71 

156 

134 

163 

43 

97 

111 

115 

118 

109 

44 

59 

71 

102 

17 

24 

186 

59 

165 

36 

37 

16 

57, 108 

130 

44 

110 

40 

111,214 

30 

97 

139, 145 

110 

42,50 

43 

83 

52 

44 

102, 105 

11 

25 

31 

54 

73 

204 

242 

114 

111 

68, 205 

60 

37 

33 

30 

162 

135, 138 

59, 113, 189 

29 

£9 

61 

67 

17 



253 



build. 



Kinneil engine, . 
Lead of slide, 
Leeds, 

Leupold, engine of, 
Liquids, expansion of, 
Load on piston, 
Locomotion, 
Locomotive engine, . 

Lafayetie, 
Geo. Washington, 
Novelty, 
Old Ironsides, 
Economy of, 
Rules for, . 
Stephenson's, 
Dunham's, 
Hodge's, . 
Norris' 
London and Glasgow steam packet, 
Calcutta, 
Engineers of, 
East water-works. 
Long, Col., 

Matthews, Mr. , truck-frame of, 
Mathesius, Sermon of, 
Maudslay, pumping engine oi 
Medicis, Cosmo De, 
Mills, Fitzgerald's proposal to 
Miller, of Dalswinton, 
Mines, ventilation of, 
Mohawk Rail-way, engines on, 
Morgan's patent paddle-wheel, 
Morris, Levi, engine of, . 
Moreland, Sir Sam]., claim of, 
Motion, rotary, first produced, 
Hull's method of, 
Fitzgerald's, 
Watt 's, 
Parallel, . 
Murdock, Mr., claim of, . 
Murray, Matthew, . 
Navigation, steam, . 

De JoufFray, 
Blasco De Garay, 
New-Orleans, steam packet to, 
Neptune, engine of, 
Newcomen, Thomas, 
Norris, W., . 
North America, boiler of, 
Oil, floating piston of, 

For lubricating piston, 
CElipile, description of, . 
De l'Orme, Philibert, 
Osceola, engine of, . 
Oxygen, supporter of combustion, 
Paddle-wheels, 

Do Cycloidal, 

Do Shaft, 

Papin, Dr. Denys, . 

Parallel motion, . , 
Rules for, . « 
Parkes, Mr. J., 
Pambour's experiments, . 
Patent, Watt's first, 
Payne's, John, experiments. 
Perkins, boiler of, . . 
Pipe, eduction, . . 

Piston, fi: st use ol, . . 



Page. Page. 

53 Piston, metallic, .... 66 
142 Load on, ... . 45, 49 

134 Velocity of, . . . .148 
31 Description of, . . .177 
84 Rod, rule for, . . .185 
45 Plates, description of, . . . 197 

t, 133 Adam Hall's engine, . . 214 

74 Allaire's, . . . 213,220 

133 Bartholomew's, . . . 205 

135 Birkbeck's, .... 204 

136 Bolton and Watt's, . . 197 

136 Cunningham's, . . . 221. 
142 Fairbairn's .... 200 
147 Maudslay's .... 200 
237 Morris', land, . . .205 
239 Marine, . . .214 

242 Peale's, .... 206 

243 Robinson and Minis', . . 229 
111 Playfair, . . . . . . 55 

111 Porta. Baptista, engine of, . . 15 
113 Portable atmospheric engine, . . 43 
113 Murray's, .... 68 

138 Watt's description of, . . 197 

137 Fairbairn's, . .200 
14 Potter, Humphrey, ... 30 

200J Power, calculation of, . . ; 31 

20 Practical rules for calculating loco- 
41 motives, .... 149 
62 Predictions of Evans. . « . 79 
40|Pressure, atmospheric, . . . 27 

137 Providence, steamboat to, . . 110 

130 Propellers, various, ... 127 

206, 214Proney, treatise of, 62 

21 Pumping engine, Cornish, . . 113 
13, 17 Quantities of water raised, . . 122 

33 Racks and sectors, ... 59 

41 Radius, rules for finding, . . 188 

46 Rafts, 124 

59 Regulator, first used, ... 27 
69 Reversing slide, .... 145 
67, 134 Robe-tson's fire-places, ... 71 
33 Robinson and Minis, engine of, . 229 
61 Robinson, Dr. J., writings of, . 69 
18 Rogers, Ketchum and Grosvenor, . 139 
110 Rolling circle, use of, ... 68 

110, 213 Roebuck, Dr., founder of, Carron 

27 Iron-works, .... 53 

133, 138, 243 Rotary motion, . . 17,33,60,68 

105, 112 Rules for calculating elastic force 
47 1 of steam, 

55| Of salt water, 

13, 17 For finding volume of, 

17; Locomotive engine, 

214 Russia, steamboat to, 
95 Safety-valve, first applied, 



33, 127 Position of, 

136! Rules for, 

180[Salinometer, account of, 
25 Salt water, analysis of, 
59 Savannah, steamboat 1 
172 Savery, Capt., 
98,Schuyler, Mr. R., . 
140, 149 Slide, lead of, . 
53 Smeaton, John, 
35 Smoke consuming furnace, 
47 Solids, expansion of, 
29 Somerset, Lord, • 
25 Speed of boats, 



147 
110 

24 
142 
166 
92 
90 
110 
22,27 
105 
142 
43 
59 
83 

110 



254 



125 
104 
109 
35 
36 
57 
56 
18,60 
22 
27 
31 
33,~62, 72, 76, 109, 123 
76 
86, 165 
92 



Page, 

168 
138 
180 
29 



Spring safety-valve, . 

Sanno, Mr. F. D., 

Shaft, fly and paddle-wheel, 

Snifting-valve, 

Split-bucket, . . . 

Screw, Archimides, . 

Stevens, Mr. R. L., 

Stevens, Mr., . . . 

Steam, density of, . 

Generation of, . 
Shutting off, . 
Expansion of, 
Force of expansion, 
Patent for engine, 
Cock, . 

High pressure engine, 
Boat, 
Wagons, 

Guage, . . . 

Expression of force of, 
Rules for finding-volume of, 
Production of, 
Expansive use of, 
High pressure expansive, 

Stuffing-boxes, 

Stuart's patent, . . . 

Sun and planet wheel, . . 

Symington, William, . . 

Table, of Morland's, 

Of the properties of various bodies, 84 
Of expansion of water. 
Elastic force of steam, 
Of boiling points of salt water, 90 
Of motion of elastic fluids, 92 

Of properties of steam, . 94 

Of dimensions of fans, . . 97 
Of comparative value of woods, 97 
Of comparative value of coal 

and wood, .... 98 
Of quantities of coal required to 

boil and evaporate, . . 99 
Chronological, of engines, . 120 
Of duty of engines, . . 121 
Of lead of slide, ... 143 
Of hyperbolic logarithms, . 162 
Of divisors for safety-valves, 165 

Thermometer, .... 84 

Throttle-valve, .... 57 

Tincroft, Mines, engine of, . . 118 

Trevithwick and Vivian, . . 73 





Pa 2 e. 


Trial of engines, . . . 


. 113 


Tubes, 


47, 140 


Ure, Dr., .... 


50 


Vacuum, .... 


22, 24, 51 


Valve, cut-off, ... 


. 112 


Snifting, ... 


29 


Throttle, 


57 


Motion of, 


68 


Mode of opening, . 


69 


Slides, .... 


. 141 


Rods, .... 


. 141 


Safety, ... 24 


, 142, 166 


Lap of, . . . . 


. 143 


Balance, described, . 


. 224 


Vapour, theory of, . 

Of alcohol, ... 


73 


61 


Velocity, increase of, . . 


. Ill 


Ventilators, .... 


40 


Versed sine, rule for finding, . 


. 188 


Vitruvius, .... 


13 


Washborough, . . 


58 


Water-work, fire 


18 


Depth of boiler, 


. 102 


Wheels, undershot, 


. 128 


Gauge, 


. 186 


Watt, James, .... 


47 


Wave formed by steamboat, . 


. 109 


Weight of locomotive, on wheels, 


. 139 


West, steamboats of, 


. 123 


Point Foundry, 


. 137 


Impediments in navigatin 




the waters of the, 


' . 124 


How obviated, . . 


. 125 


Boilers of steamboats, . 


. 105 


Engine of, . 


. 229 


Wheel, fire, .... 


25 


Carnages, . . . 


48 


Paddle, 


33, 127 


Locomotive, 


. 139 


Sun and planet, . . 


58 


Fly, .... 


. 180 


Whirling celipile, . . . 


14 


Whistle, steam, . . . 


. 187 


Wicksteed, Mr., experiments of, 


. 113 


Wilkins, Bishop, , . 


17 


Wolf, engine of, . . . 


74 


Worcester, Marquis of, . 


18 


Vork water-works, ... 


41 


Zigler, memoir of . . . 


. 59 



DEC 81939 



LIBRARY OF CONGRFQQ 

llMMIlifl* 
^029822403 3 



